Just two weeks ago, I faced the QuickBooks Multi-user Error: Network Diagnostics failed on my system. I went over the web to find some solution to it and got these steps that helped me to resolve the issue.
- Open the Run window and search for services.msc.
- Look for the QuickBooksDBXX service and check if the last two digits match with your QB Desktop version.
- If you have a different version, then install the appropriate version and check if the error is gone or not.
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