Learning Forum

[mcmasterslj]

I recently deployed Ansys 2025 R1 to all our labs and it seems to work fine from my testing, however, it seems to conflict with Excel after I install Ansys.  When we open Excel (Microsoft® Excel® for Microsoft 365 MSO (Version 2502 Build 16.0.18526.20546) 64-bit ) we receive the following error:

Name:
From: file:///C:/Program Files/ANSYS Inc/v251/optiSLang/lib/optiSLangExcelAddIn.vsto
************** Exception Text **************
System.Deployment.Application.InvalidDeploymentException: Exception reading manifest from file:///C:/Program%20Files/ANSYS%20Inc/v251/optiSLang/lib/optiSLangExcelAddIn.vsto: the manifest may not be valid or the file could not be opened. ---> System.Deployment.Application.InvalidDeploymentException: Manifest XML signature is not valid. ---> System.Security.Cryptography.CryptographicException: The form specified for the subject is not one supported or known by the specified trust provider.
at System.Deployment.Internal.CodeSigning.SignedCmiManifest.Verify(CmiManifestVerifyFlags verifyFlags)
at System.Deployment.Application.Manifest.AssemblyManifest.ValidateSignature(Stream s)
--- End of inner exception stack trace ---
at System.Deployment.Application.Manifest.AssemblyManifest.ValidateSignature(Stream s)
at System.Deployment.Application.ManifestReader.FromDocument(String localPath, ManifestType manifestType, Uri sourceUri)

--- End of inner exception stack trace ---
at Microsoft.VisualStudio.Tools.Applications.Deployment.ClickOnceAddInDeploymentManager.GetManifests(TimeSpan timeout)
at Microsoft.VisualStudio.Tools.Applications.Deployment.ClickOnceAddInDeploymentManager.InstallAddIn()

I was able to solve it for a single user with this workaround: https://install.simutechgroup.com/error-exception-reading-manifest-from-file-filecprogram-filesansys-incv251optislangliboptislangexceladdinvsto

However, is there a lab approach to resolve this issue for all users?

[Andreas Grosche]

Hello, this is a known bug - something went wrong with file signatures for the Excel Addin in 2025R1. The good news is: it was fixed with the ServicePack, so please deploy the service pack, too.

[mcmasterslj]

Thank you, that did the trick!