Hi Derek,
Welcome to Microsoft Q&A.
Please help check below questions so we can narrow down the issue
1) Is there any difference between the problematic machines and other machines? For example, what changes had been made before the issue started? (Patch, hardware, application update and so on. )
2) Does “idle for over 15 minutes” mean not using the app for 15 minutes or your machine sleeps for 15 min?
3) Have the machines joined domain?
Troubleshooting tips are as follow:
- Check network stability using following command
ping <IP address> -t
stop ping by closing the window or press ctrl+c - Try Clean Boot to see if the issue still happens, steps are as follow
Force the machine to reboot --> keep pressing F8 --> into Advanced Boot Options --> select Safe Mode --> refer to the link below to do clean boot in safe mode
https://support.microsoft.com/en-us/help/929135/how-to-perform-a-clean-boot-in-windows - Open Windows Defender Firewall in control panel, find the problematic app and check permissions.
- Check if there is any application error message in event log, especially at the time when the issue happens.
- Try log in with both administrator account and other user accounts on problematic machines, see if there’s a difference.
Please remember to mark the reply as answer if it helps.
Best regards,
Molly