System.InvalidOperationException: This implementation is not part of the Windows Platform FIPS validated cryptographic algorithms. at System.Security.Cryptography.SHA1Managed..ctor() at ....
When I say “learnt”, it was more about reading documents to determine what happened to cause the above error.
I suspect either of these:
- Microsoft have released a new schannel.dll which removes and/or breaks SHA1 functionally.
- The Group Policy setting “System cryptography: Use FIPS compliant algorithms for encryption, hashing, and signing” has been enabled.
My quick “fix” was to change the application to use a different hashing algorithm.
- System cryptography: Use FIPS compliant algorithms for encryption, hashing, and signing” security setting effects in Windows XP and in later versions of Windows
- FIPS validated cryptographic algorithms in .NET
- NIST: Secure Hashing Standards Validation List
- Microsoft: FIPS 140 Validation
- Microsoft: AES Provider Algorithms