Hi @CY ,
If I install the latest version, will it not affect the program linked to the existing SQL server 2012 express database?
No. It won't. It will works well.
You can download the latest one or if you don't want to test with the neweast version, please try SSMS v17.9, I have already tested on my side. It works fine. Please choose the version and download here: release-notes-ssms
BR,
Mia
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