Hello @David
It will be highly recommend that you post this question to the forums of the community of the manufacturers, since it is a 3rd Party product (not Microsoft) and their community will be better experienced and knowledgeable to help you in their specifics.
On general lines I can recommend the next:
- Reset your router
- Ensure that TPCIP settings are correct (or you are using DHCP settings)
- Ensure that you can ping the Router
- Access the router by it's IP address instead of URL (web portal may be deactivated
- Enable the Windows Feature SSH app (from Add Features) in case you need to SSH to the device for additional webserver settings. Once enabled you can use the "SSH <host>" command in PowerShell to create a shell connection.
Hope this helps with your query,
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