Each installation will need to address the keygen service at https://api.keygen.sh/ so the client will need to whitelist that url if required.
In the unlikely event that you suspect a problem connecting to the above address, you can run this command file to test - ping-keygen.zip.
It will output pingreport.txt to C:\Users\USERNAME\AppData\Local\Temp. Look for the line < HTTP/1.1 200 OK to confirm connectivity.
A successful connection looks like this:
* Trying 3.220.57.224:443... * Connected to api.keygen.sh (3.220.57.224) port 443 * schannel: disabled automatic use of client certificate * ALPN: curl offers http/1.1 * ALPN: server did not agree on a protocol. Uses default. * using HTTP/1.x > GET /v1/ping HTTP/1.1 > Host: api.keygen.sh > User-Agent: curl/8.4.0 > Accept: */* > < HTTP/1.1 200 OK . . .
An example of an unsuccessful connection looks like this:
* Trying 205.139.110.212:443... * Connected to api.keygen.sh (205.139.110.212) port 443 * schannel: disabled automatic use of client certificate * ALPN: curl offers http/1.1 * schannel: next InitializeSecurityContext failed: Unknown error (0x80092012) - The revocation function was unable to check revocation for the certificate. * Closing connection * schannel: shutting down SSL/TLS connection with api.keygen.sh port 443 curl: (35) schannel: next InitializeSecurityContext failed: Unknown error (0x80092012) - The revocation function was unable to check revocation for the certificate.