What do you mean registering? Normally you should select the SQL server, the Auth type and type in the correct credentials…that’s all
Will it affect the already registered server in the local administrator profile?
will this help my case.
sp_addsrvrolemember [@loginame =] ‘admin1′, [@rolename =] ‘sysadmin’
This command should be executed from administrator account which is currently having the access to the sql server?
No, that SQL Code will add another user to the sysadmin role.
Registering additional servers in Enterprise Manager won’t change the other registrations that you have setup already.