After installing the security Windows Updates released in September or October 2016, outgoing HTTPS connections from Veeam server to vCenter and NetApp storages may fail with
The request was aborted: Could not create SSL/TLS secure channel.
Any other HTTPS connections may be affected as well.
After installing one or more of the following security updates:
2012 R2 and Windows 8
2008 R2 and Windows 7
If the public key length is shorter than 2048 bytes (e.g. RSA 512), Windows may cancel the HTTPS connection.
To fully resolve the problem, regenerate vCenter or NetApp certificates so that the public key length is at least 2048 bit.
Please note that KB3172605 update causes issues with SHA-1 certificates even with the longer public key. For that one, you may want to generate the SHA-2 certificate.
As a workaround you can uninstall the updates if you have them installed.