How to FIX SQL Server Error 21089 - Only members of the sysadmin fixed server role can perform this operation

Question

I am getting SQL Server Error 21089
 
 The Error Message says :
 
Only members of the sysadmin fixed server role can perform this operation.
 
 
 Any suggestions [ Solution | TIPS ]  to resolve [FIX] this ?
 
  This is SQL Server Severity 16  Message
 
 
 Thanks

Answer 1

security issue, logon to Windows Domain, both Windows and SQL server...