This happens when Web Connector can’t find the file it needs to work. This file is QWCLog.txt.
What you can do:
To fix this, go to that QWCLog.txt file and correct its permissions. Here’s how.
1. Open File Explorer in Windows.
2. To find the QWCLog.txt file, go to this folder: C:\Users\Public\AppData\local\IntuitQuickBooks Web Connector\version directory
3. Find the QWCLog.txt file, then make sure it’s not write-protected.
4. Open Web Connector to make sure the error is fixed.
Note: If you still get this error, reach out to Intuit Support.