SIM failed to start ITMS upgrade with error "Failed to impersonate user 'Domain\username' for database validation". Error is thrown almost immediately after clicking on Next button to proceed with upgrade.
Issue observed randomly over the years on various versions of SIM. Latest observation was on SIM 8.1
Failed to impersonate user 'DOMAIN\USERNAME' for database validation. Try again or contact support if this problem persists.
Exception occurred while impersonating user. Some or all identity references could not be translated.
[System.Security.Principal.IdentityNotMappedException @ mscorlib] at System.Security.Principal.SecurityIdentifier.Translate(IdentityReferenceCollection sourceSids, Type targetType, Boolean forceSuccess)
at System.Security.Principal.SecurityIdentifier.Translate(Type targetType)
at Symantec.Installation.InstallClasses.SQLAuth.VerifyDBPermissions(String dbname, Boolean createNew, Int32 timeout, Boolean& bTempdbAutogrow)
This issue has been addressed in a recent update with SIM. The fix has been included starting SIM 8.1.5037 and later (ITMS 8.1 RU1 (DOC10474)).