NetExtender - Windows Proxy - Microsoft Apps and Authentication Issues

I started a ticket with support regarding this issue, but it is good to get a conversation started as well.
After a user connects to the VPN via Net Extender then returns to the office, they are unable to use any product that uses the Microsoft Authentication Library (MSAL) for authentication. This includes the Office 365 suite, Teams, Word, OneDrive, Excel, etc... The apps behave like they don't have access to the internet. However, web versions in a web browser still work fine.
After many, many hours of troubleshooting, it was discovered that enabling then disabling the proxy setting in Windows settings fixes the issue. Restarting the computer does not solve it, uninstalling/reinstalling Net Extender does not fix the issue, uninstalling/reinstalling Office products does not fix the issue. The original fix was to reinstall Windows, then it was discovered that enabling the proxy with the settings blank/default, then turning it back off in Windows solves it. This is our current workaround, but this is a problem that needs addressed.
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We've got the same issue. Still trying to find the root cause of it.
Hoping to find a fix that can be done from our end rather than something that has to be done from the users end/PC. We will most likely be opening a ticket as well.
Following this thread. Glad it's not just us!
We still haven't been able to connect with SonicWall regarding this. We are waiting to have a machine that comes in with the issue that we can work with for a while, so we can call in for some screen sharing / packet sniffing with SonicWall support.
A couple of things we found:
Often, when we would run Fiddler during the problem, the issue would go away until we closed Fiddler.
One time, running Fiddler actually solved the problem.
The issue is few and far between, but it has always been on Dell laptops and seems to be happening to the same people.
We’re also noticing it mostly with the same people, and mostly laptop users. (But that could just be due to the fact that laptop users are more likely to use NetExtender than PC users). It seems to be people who work from home and then come back onto site. It’s at the point that they physically come back onto site that it breaks.
These are the two fixes we're currently using. Let me know if they work for you if you get a chance to test them.
The quickest fix we have for this is as follows:
(The below scenarios assume the user is physically on-site).
The alternative, but longer, fix is as follows:
(Rebuilding the Windows profile).
We have also tried the following which do not resolve the problem:
We’re now certain this is a NetExtender issue and SonicWall will need to push out a new version to fix it.
just curious... Have you tried the method of enabling then disabling the proxy in Windows network settings?
In our experience, just enabling, saving, then disabling fixes it. I would still point to NetExtender as well.
Settings -> Network & internet -> Proxy "Set up" -> toggle the Use a proxy server button, Save -> Then untoggle and save.