Two weeks ago, I found one of my clients encountering an interesting issue where he found that the SQL server management studio (SSMS) works only when it is launched as an Administrator. But if it is launched as a normal user, SSMS does not work and throws exception.
On launching SSMS as an user, even a simple action such as opening a new query window also threw an exception.
Based on the error message, on research figured out it might be an issue with the User Access Control and thus tried disabling it referring to the article - https://docs.microsoft.com/en-us/windows/desktop/secauthz/user-account-control. Though it did not resolve the main issue, but directed the issue to show up a more precise exception.
Thus, took a process monitor trace and found that it was an issue due to lack of permissions on multiple folders which showed up in the trace and by providing full permissions on those folders helped us rectify the SSMS issue. Now it is not required to open SSMS as an administrator for its required working.
Hope this helps !! Happy resolving !!