There are a few ways to open SQL Server Managaement Studio as another Windows user. My usual approach is to create a shortcut on my desktop that uses the built in ‘Runas.exe’ command.
In notepad I assemble the 3 parts needed …
1. Full path to runas.exe
2. The Windows account I want to use
3. The full path to the SSMS executable.
Here is an example …
C:\Windows\System32\runas.exe /user:ZGROUP\rsmithadmin "C:\Program Files (x86)\Microsoft SQL Server Management Studio 18\Common7\IDE\Ssms.exe"