VPN (SonicWall) will not connect over T-mobile 5G Hotspot

I found a post about turning off IPv6 on my WiFi connection on my Windows laptop that resolved this issue for me.

The issue I was having was that from my Windows laptop, I was NOT able to VPN into my workplace using my personal hot-spot thru my iphone 12 (I’m running iOS 15.1.1) using TMOBILE.

To resolve the issue, I had to disable IPv6 on my Wireless connection on my laptop.

Do disable IPv6 on my Wireless connection on my Windows laptop I did these steps:

1. Open “Network and Internet Settings”
2. Under “Advanced Network Settings”, Click on “Change adapter options”
3. It will bring up a list of Network connections, double click on the one that says “Wi-Fi”
4. In the new dialog box, click on “Properties” bottom left, do NOT click on “Wireless Properties”
5. The next dialog box will have a list of "This connection uses the following items”
6. Scroll down in that list to find “Internet Protocol Version 6 (TCP/IPv6)”, this will be in the list after the “Internet Protocol Version 4 (TCP/IPv4)”.
7. Uncheck the box in front of “Internet Protocol Version 6 (TCP/IPv6)”. Leave the IPv4 checked.
8. Hit “OK”

After I did these steps I was able to use the VPN client (in my case it is the FortiClient VPN) and I was able to successfully VPN thru my hot-spot thru my TMOBILE service.

I also went back and retested using a normal WiFi connection (thru my home network) and everything still worked in that case too.