I just recently downloaded WARP and it was working perfectly until the last update. I uninstalled it and deleted all cache and temp files then installed old version. It still not working and I am getting this error message: We were unable to register your client with WARP. If anyone knows a possible solution please share with me.
i also have same problem
For me the issue was that the update binaries were too new and unrecognised, so they were blocked by AV.
My solution was to temporarily disable real-time protection, cleanly install and update Warp from scratch, then (after it was working/configured and up to date) reenable real-time protection.
I think many other things could cause this issue though, I assume tools like web filters or virtual network adapters (anything that might use loopback connections or mitm web sessions etc)