Follow-up: apply crypto security-warning comments to snippets skipped in #12524 due to build infra

Start by reviewing PR #12524 and the Snippets 5000 build failures for the listed C# and Visual Basic files. Check which snippets lack project files or fail assembly and target-framework resolution, then apply the corresponding security-warning comments once the snippets are wired into the pipeline. Done means the affected snippets build successfully and have parity with the C# updates from #12524.

[!NOTE]
This issue is AI-generated as follow-up work from PR #12524.

Snippets skipped for security-warning updates due to CI infra

While rebasing PR #12524 (NIST-approved crypto recommendations), the following snippet files could not receive the intended security-warning comments because touching them triggers pre-existing Snippets 5000 build failures unrelated to the change:

Type/assembly resolution failures (CS0234 / CS1069 / CA5372 / signing errors):

• snippets/csharp/System.Security.Cryptography/AsymmetricAlgorithm/Overview/customcrypto.cs — CustomCrypto.snk file missing (CS7027), duplicate AssemblyVersion attribute
• snippets/csharp/System.Windows.Forms/DataGridView/CellContentClick/employees.cs — System.Windows.Forms.* not on target framework
• snippets/csharp/System.Xml.Xsl/XslCompiledTransform/Overview/Xslt_Transform_v2.cs — XslCompiledTransform.TemporaryFiles (removed in .NET Core)
• snippets/csharp/VS_Snippets_CFX/s_ue_httpdigestclientcredential/cs/source.cs — System.ServiceModel.* unavailable
• snippets/csharp/VS_Snippets_CFX/s_ueclientcredentials/cs/program.cs — same
• snippets/csharp/VS_Snippets_CFX/s_uex509certificatevalidationmode/cs/client.cs — same
• snippets/csharp/VS_Snippets_CFX/windowsclientcredential/cs/source.cs — same
• snippets/csharp/VS_Snippets_WebNet/System.Configuration.ProtectedConfigurationProvider/CS/ProtectedConfigurationProviderLib.cs — System.Configuration.ProtectedConfigurationProvider forwarded to unreferenced assembly

"Project missing" (no .csproj / .vbproj alongside the file):

• snippets/csharp/System.Security.Cryptography/DESCryptoServiceProvider/CreateEncryptor/{file,memory}example.cs
• All VB counterparts touched by the PR, including:
  • snippets/visualbasic/System.CodeDom/CodeChecksumPragma/Overview/codedirective.vb
  • snippets/visualbasic/System.Security.Cryptography/**/{customcrypto,members,file/memoryexample,source,sample,class1,rfc28981}.vb
  • snippets/visualbasic/VS_Snippets_CFX/s_ueclientcredentials/vb/program.vb
  • snippets/visualbasic/VS_Snippets_Data/*/VB/*.vb
  • snippets/visualbasic/VS_Snippets_WebNet/System.Configuration.ProtectedConfigurationProvider/VB/ProtectedConfigurationProviderLib.vb

Follow-up

Once these snippets have working project files (or are wired up correctly for the Snippets 5000 pipeline), the same NIST-approved / hardcoded-credential / DES-insecurity comments landed in the C# equivalents in #12524 should be applied here for parity. The comment payload is trivial — the blocker is purely CI.