PR_CONNECTION_RESET_ERROR only happening @ one provider
I am trying to find a problem which suddenly appeared today. We have not changed any configurations at our network.
Suddenly websites, hosted at one austrian provider, where our homepage is hosted do not open anymore.
Only giving a: PR_CONNECT_RESET_ERROR in Firefox and do not open in Edge too.
Sites are doing this, when I try via curl:
curl -vv https://www.pc-howto.com
* Rebuilt URL to: https://www.pc-howto.com/
* Trying 126.96.36.199...
* TCP_NODELAY set
* Connected to www.pc-howto.com (188.8.131.52) port 443 (#0)
* schannel: SSL/TLS connection with www.pc-howto.com port 443 (step 1/3)
* schannel: checking server certificate revocation
* schannel: sending initial handshake data: sending 181 bytes...
* schannel: sent initial handshake data: sent 181 bytes
* schannel: SSL/TLS connection with www.pc-howto.com port 443 (step 2/3)
* schannel: failed to receive handshake, SSL/TLS connection failed
* Closing connection 0
* schannel: shutting down SSL/TLS connection with www.pc-howto.com port 443
* Send failure: Connection was aborted
* schannel: failed to send close msg: Failed sending data to the peer (bytes written: -1)
* schannel: clear security context handle
curl: (35) schannel: failed to receive handshake, SSL/TLS connection failed
If I try outside our network (without our Fortigate) it works.
If I turn off all filters @ the policy used for my client the connection is still not working.
I am running out of ideas now.
Any help, hint or tip is very welcome....