Activation error on production server - FIPS compliance
We have thoroughly studied the problem and here are our conclusions.
- We can’t move from MD5 to another FIPS-complaint hash algorithm because the PDF standard relies on MD5 with no alternative.
 - Replacing .NET implementation (
System.Security.Cryptography.MD5) with any other implementation in plain source code is not a solution, as it will be even less FIPS-compliant. 
Workable solutions:
- Move your project to .NET Framework 4.8 that uses relaxed policy and will not through an exception in FIPS environment.
 - Add 
UseLegacyFipsThrowswitch to your application config file. It will disable the exception: 
<configuration>
 <runtime>
    <AppContextSwitchOverrides value="Switch.System.Security.Cryptography.UseLegacyFipsThrow=false" />
  </runtime>
</configuration>
Please check this related Microsoft article: https://docs.microsoft.com/en-us/dotnet/framework/migration-guide/retargeting/4.7.2-4.8
To get Activation.exe work on your server please email our support team.