iPhone 6s won't connect to VPN on work wifi but will on other wifi networks

VPNs can be tricky, may have to consult with Betternet. Also check this article for suggestions.

iOS: Setting up VPN - Apple Support

FWIW below are some general recommendations for Wi-Fi issues, maybe one of them will help.

1) Perform a Forced Restart: Hold down the Home and Wake/Sleep buttons at the same time for about 15-20 seconds until the Apple logo appears. Allow device to restart.

2) Reset Network Settings: Settings > General > Reset > Reset Network Settings. Rejoin the Network again.

3) Reboot Router/Modem: Unplug from power for 2 minutes and plug again. Update Router Firmware (check manufacturer’s support website for a newer FW). Also try different bands (2.4 GHz and 5 GHz) and different bandwidths (20 MHz recommended for the 2.4 band).

4) Change to Google's DNS: Settings > Wi-Fi > Click on the Network, Delete all numbers under DNS and enter 8.8.8.8 or alternatively 8.8.4.4

5) Disable device prioritization on the router if this feature is available.

6) Determine if other Wi-Fi devices on network are working well (other iOS devices, Macs, PCs).

7) Try device at another Network, i.e., neighbors’, public coffee house, etc.

8) Restore the Device (ask for additional for details if desired).

https://support.apple.com/en-us/HT201252

9) Go to an Apple Store for hardware evaluation.

DynDean wrote:

could the IT people have changed the settings on the router to stop VPN connections to servers other than their own? If so is there any way around this?

I suppose it is possible, I would ask them. And if so, no, I do not know a way around, sorry.

I have the same problem. iPhone 6 can tether to a laptop and be used to get VPN access remotely. iPhone 6s can only get internet for tethered laptop. Can't provide VPN access. Dell says its Apple, Apple says its ATT and ATT says its Sonicwalls fault. No one knows how to fix it. If you untether the iPhone 6s it works once you plug it back in it doesn't.

DynDean wrote:

The frustrating thing is that is worked perfectly fine until recently, could the IT people have changed the settings on the router to stop VPN connections to servers other than their own? If so is there any way around this?

It's highly likely, and probable. There's a reason IT doesn't want you to access certain apps from within the office, and they discovered you were getting around their block, so they tightened it up. There are probably ways around it using a VPN that uses different ports, but you are presumably violating IT security policy, so if you continue there may be other repercussions beyond just blocking your access.

You will have to view the specs for different VPN services, and find ones that use different ports. It will likely not be any of the major providers. This might work, once it becomes available: https://www.indiegogo.com/projects/keezel-online-freedom-for-every-device-everyw here/#/

Another option is to not use WiFi; use cellular data.