Thanks for posting.
Please notice that we don't support issues related to VPN as these applications replace our drivers.
However, in order to confirm if there's something we can help you with please provide us with the following information:
- VPN software used.
- Router model.
- https://downloadcenter.intel.com/download/25293/Intel-System-Support-Utility-for-Windows-?product=91... Intel® System Support Utility file. Please scan everything and save the file in your system.
- WLAN Interface information before and after connecting to VPN:
Please attach the resulting files to your next reply.
Thanks for the information.
Reading online, other users have reported similar issues while using Sonicwall Global VPN*. There's one that offers a solution:
- https://community.spiceworks.com/topic/2096371-global-vpn-client-greatly-slows-internet-when-connect... Spiceworks* Communities - Global VPN Client greatly slows internet
Even though the issue seems to be at layer 3 and linked to the VPN client, please try a driver only installation just to discard this option:
1. Download and extract our latest IT Admin driver package for your adapter: https://downloadcenter.intel.com/download/27485 WiFi_20.30.1_Driver64_Win10.zip
2. Under Programs and Features in the Control Panel, or Apps & Features in Windows* Settings, uninstall any instance of the "Intel® PROSet/Wireless Software." When prompted, choose to "discard settings."
3. Go to the Device Manager > Network Adapters > Right click on your Intel(R) Dual Band Wireless-AC 8265 and uninstall it. Make sure to mark the option to "Delete the driver software for this device."
4. Clear out your temporary files: Press the Windows* Key + R to open the run box. Type Cleanmgr.exe and press OK. Here you will need to make sure Temporary Files are checked, you may uncheck everything else, then press OK.
5. Reboot your computer.
6. Go to the Device Manager > Network Adapters > Right click on your Intel(R) Dual Band Wireless-AC 8265 again, this time choose to "Update driver software..." > Select the option to "Locate and install driver software manually." Here you will need to direct the wizard to the location where you extracted the IT Admin package back in step one.
Please https://www.sonicwall.com/en-us/support/knowledge-base/170505704468100 reinstall the VPN client as well. If the issue persists, please contact https://www.sonicwall.com/en-us/support/support-services Sonicwall* support for further assistance.
NOTE: Links to third party sites are being offered for your convenience and should not be viewed as an endorsement by Intel of the content, products, or services offered there.
Let us know if there's anything else we can do for you.