Windows blocked?

[le Pingouin]

It could be as simple as a graphics pop-up relying on the user credulity to ring the number and allow remote access.

https://answers.microsoft.com/en-us/...1-64aac2f5914c

It could also be malware so I'd suggest following this rather thorough extermination regimen:

https://www.bleepingcomputer.com/vir...n-blocked-scam