SSMS - Assembly error after upgrade to new version

I was running an upgrade on SSMS and it won't connect to the SQL Server after installation. I can connect to the SQL Server from SSMS on another server but not on the local one.

I'm getting the following message when I try to connect:

Could not load file or assembly 'Microsoft.AnalysisServices, Version=19.2.0.2, Culture=neutral, PublicKeyToken=89845dcd8080cc91' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040) (ObjectExplorer)

I tried uninstalling and reinstalling SSMS but I'm getting the same error. I'm hoping there's a fix that doesn't require a restart. This server only goes down for a couple hours a month for maintenance.

The issue is not with SSMS itself. The problem is with SQL_AS_AMO install. It seems like your Microsoft.AnalysisServices is corrupted no longer valid.

Download and reinstall the Analysis Services client libraries to repair your SQL_AS_AMO https://docs.microsoft.com/en-us/analysis-services/client-libraries?view=azure-analysis-services-current (Look for the AMO link)