When SingleOps syncs data to QuickBooks Desktop (QBD) through the Web Connector, QuickBooks may reject a record and return an error code. This article explains the most common QBD sync error codes you'll encounter, what causes them, and how to resolve them so your data syncs successfully.
In this article:
How & Where?
How to read these errors: | These are QuickBooks Web Connector (QBWC) errors from syncing between SingleOps and QuickBooks Desktop.
The QBWC error log names the exact record (customer, job, invoice, or item) that failed — always start there.
Read the information displayed under the LATEST MESSAGE column for more details on the error. Most fixes end by attempting a Resync and re-running the Web Connector. |
Where to find your errors: | Open the QuickBooks Management Center to see the exact record that failed and its full error text.
Here where you can Clear ID and re-run affected records. Always match on the full error message, not just the code number, before applying a fix. |
Quick-Reference Index
Use this table to find your error code and first action, then jump to the detailed section below for full steps.
Code | What it means | First Action |
3000 | Deposit/payment/invoice violates a QBD data rule (mapping, A/R, bank) | Fix the account mappings in QBD, then re-run the Web Connector |
3020 | Corrupted or out-of-range FromModified date on the connection | Escalate to Customer Support to reset the date setting on the backend. Once completed, we will have you re-run the Web Connector |
3060 | Line item uses an item type that doesn't accept a quantity | Remove the quantity from unsupported items, then re-run the Web Connector |
3100 | Duplicate name — a client/entity with that name already exists in QB (usually created in both systems) | Check whether the same client was created in both SingleOps and QB.
Rename one slightly, or if they're the same customer, merge the records in SingleOps, then retry. |
3120 | A record SingleOps is updating was deleted, renamed, or altered in QB, so the stored link no longer points to anything. | Find the named record in QB and confirm it exists/matches.
Use Clear ID on the error, then re-run the Web Connector.
Note this sends a NEW record to QB, so confirm the original is truly gone/unlinked first to avoid duplicates |
3140 | An item is mapped to an invalid account (Sales Tax Payable, Undeposited Funds, A/R, A/P, or a non-posting account). | Open the item named in the error.
Assign it to a real income or expense account (income if you sell it, expense if you buy it), then retry. |
3140 / 3250 | Tax locations/groups or item tax codes don't line up between systems | Verify and map tax items in QBD (apply the Canadian settings), then retry |
3170 (ItemService list) | Duplicate or conflicting item/service name between QB and SingleOps | Make item names unique, confirm single-user mode, then retry |
3170 (dividing date) | Transaction Dated On or Before the Dividing Date | Wait for the accountant's merge, or ask Support to change the TxnDate |
3171 | Attempt to modify an invoice dated on/before the company's closing (closed-books) date | Check the invoice date against the QB closing date.
Make the change manually in QB, change the invoice date to outside the closed period, or reopen the books for that range, then retry. |
3175 | Target record is open or locked by another QBD user/session | Have all QBD users close the named records, then re-run the Web Connector |
3210 | Payment applied is greater than the amount due on the invoice | Compare the payment amount to the invoice total.
Check the invoice total in SingleOps vs. QB; if they differ, report it to Support.
Otherwise correct the payment/invoice amounts and retry. |
3250 | A field/feature being synced isn't supported in that QB version — most often item operation | Confirm the account is trying to sync item operations.
Set the account setting "Sync Item Operation for QBWC" to false, then retry. |
3260 | Insufficient permission — the QB user the connector was set up with lacks rights for the action. | Confirm which QB user authorized the connector. |
3391 | The iteratorID is invalid — a sync of a large result set was interrupted and couldn't resume. | Close and restart the Web Connector.
If it persists, open Task Manager and "End process" on anything QB-related, then relaunch; SingleOps resumes automatically. |
0x80040400 | Low-level XML parse error; usually a data error that didn't make it cleanly through the connector (not user-caused). | Click Retry or Resync.
If retry doesn't clear it, create a support request for investigation. |
ReceiveResponseXMLFailed (QBWC1042) | The Web Connector called back to the SingleOps endpoint and got an HTML page (error/maintenance/gateway) instead of XML, so it can't parse the response. | Re-add a fresh QWC file; if it still aborts, collect the log and escalate |
3200 - Edit Sequence | A record was changed in both SingleOps and QuickBooks between syncs, so the edit sequence SingleOps has on file is out of date and QBD rejects the update. | In SingleOps, go to Reports > QB Syncing, check the affected record(s), and click Fix Edit Sequence for checked, then re-run the Web Connector. |
Detailed Error Code Resolutions
Error 3000 — Data Validation Error
Error message: "QuickBooks Desktop Error Code 3000" when syncing deposits or invoices.
Cause: A deposit, payment, or invoice from SingleOps violates a data rule in QuickBooks Desktop — for example, a wrong target account, an invalid A/R or bank mapping, or a referenced list object that doesn't meet QBD constraints.
Resolution: Compare the SingleOps transaction with the intended QBD configuration: confirm the correct A/R or bank account, ensure the customer is active, and verify all items and tax codes are valid in QBD. Correct the mappings in QBD, then re-run the Web Connector.
Error 3100 — Duplicate Name
Error message: "Unable to create: QBWC ERROR: 3100 — The name 'item name' of the list element is already in use." (Also seen as: "Unable to update Client with name 'John Smith' in SingleOps: Name has already been taken.")
Cause: QuickBooks does not allow two different entities to share a name. This usually happens when the same client is created separately in both SingleOps and QuickBooks — the two records don't match and can't sync because of the duplicate name.
Resolution:
Confirm the client or item was created in both systems rather than allowed to sync across.
Rename one of the records slightly so the names no longer collide.
If they are truly the same customer, merge the records in SingleOps to prevent further errors, then re-run the Web Connector.
Going forward, avoid creating the same client in both systems.
Error 3120 — Object Cannot Be Found
Error message: "Unable to create: QBWC ERROR: 3120 — Object specified in the request cannot be found. QuickBooks error message: Invalid argument. The specified record does not exist in the list."
Cause: SingleOps is trying to sync to a customer, job, invoice, payment, or item whose underlying QBD record was deleted, made inactive, or no longer matches the stored list ID in QBD.
Resolution:
In QBD, find the customer, job, item, or transaction named in the QBWC error log and confirm it exists and is active.
If it was deleted or replaced, recreate or relink the SingleOps record as needed. Use Clear ID on the error row in SingleOps, then re-run the Web Connector.
⚠️ Clear ID sends a NEW record to QuickBooks as if one never existed there. Confirm the original is actually missing first, or you'll create a duplicate. |
Error 3020 — Invalid FromModified Date
Error message: "Unable to sync: QBWC ERROR: 3020 — There was an error when converting the date value '1969-12-31T18:50:00-05:00' in the field 'FromModified date'."
Cause: The Web Connector's stored FromModified date for the QBD–SingleOps connection is corrupted or out of range — often after a QBO→QBD migration or reconnect — so QuickBooks rejects the sync range.
Resolution:
Follow Collecting the QBWC Log and submit the QuickBooks Log File to support@singleops.com
The SingleOps Support Team needs to be involved in order to reset the FromModified window.
Once the SingleOps Support Team confirms the reset, a member of our team will reach out to have you re-run the Web Connector until it completes without the errors.
Error 3060 — Quantity Not Supported for Item Type
Error message: "Unable to create: QBWC ERROR: 3060 — There was an error when converting the quantity '1.0' in the field 'item quantity'. QuickBooks error message: You cannot set the quantity for items of this type."
Cause: A line item in the invoice or payment uses a QuickBooks Desktop item type that doesn't support quantities (for example, certain non-inventory/service items or group behavior), but SingleOps is still sending a quantity, so QBD rejects the transaction.
Resolution:
From the QuickBooks Management Center, identify which invoice and item are failing.
In SingleOps, open the job/invoice and locate the problematic item (sometimes found inside an item group) where the quantity is 1. The item will need to be modified in QBD, if possible, or swapped out
The error relates to the items Type in QuickBooks Desktop. QuickBooks Desktop allows for Once an item begins producing this error, it should be replaced with a newly created item that is set up correctly so quantity is only used on quantity supported items. Most commonaly occurs when an item has been updated from Service Type to Non-Inventory Part.
In QuickBooks Desktop - Items should be set to type Service or Discount
Once the item has been swapped out / updated on the invoice producing the error:
Save the changes
Press Sync to QuickBooks either from the Job or Resync the error from the QuickBooks Management Center
Then re-run the Web Connector.
Error 3140 — Invalid Account Reference on Item
Error message: "Unable to create: QBWC ERROR: 3140 — There is an invalid reference to QuickBooks Account '...' in the Item Service. QuickBooks error message: You cannot associate an item with Sales Tax Payable, Undeposited Funds, accounts receivable, accounts payable, or non-posting accounts."
Cause: SingleOps is trying to sync an item mapped to a restricted account type (A/R, A/P, Sales Tax Payable, Undeposited Funds, or a non-posting account) instead of a real income or expense account.
Resolution:
Open the item named in the error and edit it.
Assign it to a valid QuickBooks income or expense account — use an income account for items you sell, an expense account for items you buy.
Save and retry the error.
Error 3170 — Error Modifying ItemService List
Error message: "Unable to create: QBWC ERROR: 3170 — There was an error when modifying a ItemService list."
Cause: Usually a duplicate or conflicting item/service name between QuickBooks Desktop and SingleOps.
Resolution:
Verify the ItemService names in both systems and make sure they are unique.
Confirm the QuickBooks company file is in single-user mode.
Retry the sync.
Error 3170 — Transaction Dated On or Before the Dividing Date
Error message: "Unable to update: QBWC ERROR: 3170 — There was an error when modifying an Invoice. QuickBooks error message: You may not create or edit a transaction dated on or before the dividing date."
Cause: The dividing date is the date you gave a copy of your QuickBooks file to your accountant. While your accountant works on invoices and estimates in that period, QuickBooks won't allow SingleOps to create or edit any transaction dated on or before the dividing date. When SingleOps tries to sync one of these records, the update is rejected and the item stops syncing.
Resolution:
Confirm the affected invoice or estimate is dated on or before the dividing date. You can review the failing records in the QuickBooks sync error list.
Wait for your accountant to merge their changes back into your QuickBooks. Once the merge is complete, the sync will be able to update these invoices/estimates and the error will clear on its own.
If you can't wait for the merge, SingleOps can alter the transaction date (TxnDate) in the SingleOps database so you can attempt a re-sync. Contact Support with an explicit list of the job numbers and the new transaction date you'd like each changed to.
Error 3171 — Invoice Dated On or Before Closing Date
Error message: "Unable to create: QBWC ERROR: 3171 — An attempt was made to modify a Invoice with a date that is on or before the closing date of the company."
Cause: The accounting period has been closed, and there is an attempt to change or update an invoice whose date falls within that closed range.
Resolution: Choose one of the following, then retry:
Make the change manually in QuickBooks Desktop.
Change the invoice date to a date outside the closed period and then Resync
Reopen the books for that date range in QuickBooks and then Resync
Error 3175 — Record In Use or Locked
Error message: "QuickBooks Error code 3175" (commonly indicates the target record is in use).
Cause: QuickBooks Desktop reports that the invoice or other record is currently open or locked by another user or session, preventing the Web Connector from updating it.
Resolution:
Ask all QBD users to close any open forms and reports — specifically the customers/jobs and invoices named in the error.
Once the record is confirmed closed (and no background tasks have it locked), re-run the Web Connector.
If errors persist, restart QuickBooks and the Web Connector, then retry.
Error 3210 — Payment Exceeds Amount Due
Error message: "Unable to create: QBWC ERROR: 3210 — The 'AppliedToTxnAdd payment amount' field has an invalid value '168.03'. QuickBooks error message: You cannot pay more than the amount due."
Cause: SingleOps is applying a payment to an invoice for more than the invoice's amount due.
Resolution:
Compare the invoice total to the payment amount.
Compare the invoice total in SingleOps against the invoice total in QuickBooks. If they differ, report the error to support@singleops.com.
Correct the amounts so the payment does not exceed the balance due, then retry
Error 3250 — Feature Not Enabled in This QB Version
Error message: "Unable to create: QBWC ERROR: 3250 — This feature is not enabled or not available in this version of QuickBooks."
Cause: SingleOps is trying to sync a field the installed QuickBooks version doesn't support. The most common trigger is syncing item operations.
Resolution: In SingleOps, set the account setting "Sync Item Operation for QBWC" to false, then retry the sync.
Error 0x80040400 — XML Parse Error
Error message: "Unable to update: QuickBooks found an error when parsing the provided XML text stream."
Cause: A low-level data error that may not have passed cleanly through the QBD Web Connector. These are not caused by users.
Resolution:
Click Retry or Resync on the error.
If retrying doesn't clear it, create a support request so the SingleOps team can investigate.
Error 3140 / 3250 — Tax Location or Tax Code Mismatch
Error message: QBD errors such as 3140 / 3250 around tax locations or item tax configuration on invoices.
Cause: The invoice or purchase uses tax locations, tax groups, or item tax codes that don't line up between SingleOps and QBD — especially in Canadian or complex tax setups — so QBD rejects the transaction.
Resolution:
Confirm whether the account is Canadian and whether they rely on combined tax groups.
For Canadian setups, reach out to us at support@singleops.com ensure the three documented account settings are in place (line-level tax flag on, "Use Item's QBO Tax Code" behavior mirrored in QBD, and line-level flag hidden in SingleOps), then we will have you retry the sync.
In QBD, verify that tax locations used in SingleOps exist as valid sales tax items/groups, and that items are mapped to the right tax codes.
Error 3260 — Insufficient Permission
Error message: "Unable to sync: QBWC ERROR: 3260 — Insufficient permission level to perform this action."
Cause: The QuickBooks user the Web Connector was set up with does not have permission to perform the action. This is typically seen when the connector was configured on a QB account without Admin-level permissions.
Resolution:
Identify which QuickBooks user account authorized the Web Connector.
Re-set up the connector under a QB user with Admin permissions, or upgrade that user's permission level.
Re-run the sync.
Error 3391 — Invalid IteratorID
Error message: "Unable to sync: QBWC ERROR: 3391 — The iteratorID '{...}' is not valid."
Cause: A sync was interrupted while processing a large result set, and the connector could not pick up where it left off.
Resolution:
Close and restart the Web Connector. SingleOps should start the sync over automatically.
If it persists, open Task Manager and End process on anything QuickBooks-related, then relaunch QuickBooks and the Web Connector.
Error QBWC1042 — ReceiveResponseXMLFailed
Error message: "QBWC1042: ReceiveResponseXMLFailed" or "Update aborted per request from application."
Cause: After QuickBooks Desktop processes a request, the Web Connector calls back to the SingleOps web service to deliver the response. Instead of the expected XML, it receives an HTML page (an error, maintenance, or gateway page). Because the Web Connector can only parse XML, it fails on the content-type mismatch.
Resolution:
Fully close QuickBooks Desktop and the Web Connector, reopen QBD as Admin, and retry the sync.
If it still fails, remove the existing SingleOps app from the Web Connector.
Download a fresh QWC file from SingleOps (Setup → Account Settings → QuickBooks → QuickBooks Desktop), re-add it, and complete authorization.
Re-run the sync. If it continues to abort, collect the QBWC log and escalate to engineering.
QBWC Edit Sequence Error ("out-of-date")
A quick note on what an edit sequence is: QuickBooks stamps every record (customer, job, invoice, payment, item) with an edit sequence — a version marker that changes each time the record is edited. When SingleOps sends an update, it includes the edit sequence it has stored so QuickBooks can confirm it's updating the current version. If that marker no longer matches, QuickBooks refuses the update.
Error Message: "Unable to update: The provided edit sequence "…" is out-of-date."
Cause: The record was changed in both SingleOps and QuickBooks in between Web Connector syncs. Because QBD syncs run on an interval (often every 5 minutes) rather than instantly, there's a window where a record can be edited on both sides — for example, SingleOps syncs an invoice over, then a payment is applied or the record is edited directly in QuickBooks before the next sync. SingleOps' stored edit sequence is now behind QuickBooks' current version, so the update is rejected.
Resolution
In SingleOps, go to QuickBooks Sync Wizard and locate the affected record(s). Check the record (or select all) and click Fix Edit Sequence for checked. This refreshes the stored edit sequence to match QuickBooks' current version so the record can sync.
Re-run the Web Connector and confirm the error clears.
Forcing Re-Syncs & Using Clear ID
When you encounter a record that will not resync, avoid repeatedly forcing it. Re-running a failed record over and over can create duplicate customers, jobs, or invoices in QuickBooks Desktop.
Clear ID
Clear ID removes the existing QuickBooks link on a SingleOps record and generates a new working list ID so the record can sync as a NEW record. Use it only when you want a new record to sync over — not to force an existing one.
When and how to use
If you cannot locate an invoice in QuickBooks that shows it previously synced, or if the invoice has been unlinked from the SingleOps version, you may want to delete it in QuickBooks before syncing new ones over.
To send a NEW record of the entity, select Clear ID under the Actions column.
This clears the list ID and generates a new, working list ID, sending NEW data to QuickBooks.
Select Resync under the Actions column.
Run your web connector to push the record through.
When to Escalate & Contact Support
Some errors require additional assistance or engineering rather than a self-serve fix — most notably 3020 (FromModified reset), persistent ReceiveResponseXMLFailed aborts, and bulk-clearing stuck records in the Sync Wizard.
If a record continues to fail after following the steps above, or if you cannot determine the correct resolution, attach the fresh QWCLog.txt and contact Support at support@singleops.com rather than repeatedly forcing re-sync
Collecting the QBWC log
The Web Connector automatically writes to a log file that shows the exact request and response exchanged between QuickBooks Desktop and SingleOps. By default, it is saved at:
C:\ProgramData\Intuit\QBWebConnector\log\QWCLog.txt
Enabling verbose logging
Verbose logging captures the full qbXML request and response for each transaction, which makes it much easier to pinpoint the failing record. To turn it on:
Fully close the QuickBooks Web Connector and QuickBooks Desktop.
Open the Registry Editor: press Windows + R, type regedit, and press Enter.
Navigate to
HKEY_CURRENT_USER\Software\Intuit\QBWebConnector.Double-click the Level value and change it to VERBOSE (the default is DEBUG), then click OK.
Reopen the Web Connector and re-run the sync to reproduce the error.
Retrieve the updated log from
C:\ProgramData\Intuit\QBWebConnector\log\QWCLog.txt.
For full details, see Intuit's guide: QBWC Logging.
Note: Editing the Windows registry can affect how your system behaves — follow the steps above exactly, and only change the Level value.
Before you submit the log
So Support receives a clean log that only contains the relevant sync run, clear the current file first: in the QuickBooks Web Connector window, select Log → Clear Log, then re-run the sync to reproduce the error. This overwrites the old entries with just the failing run.
