Can't make a new Login

Hi,
I have this problem:
When I create a new Login with a "SQL server authentication".
And if I change some User Mapping and Server Roles it gives me the follow
message "Create failed for User 'win2kadmin "
Server Name: SERVER\SERVER
Error Number: 15023
Severity: 16
State: 1
Line Number: 1
I will be gratful if you can help me,
--
Thanks ,
PeterThat error means the user, group, or role already exists. You will need to
drop the current user before creating the new one.
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"Pedro" <Pedro@.discussions.microsoft.com> wrote in message
news:34092E0F-DBB2-4DD4-BFE7-27E323E7A606@.microsoft.com...
> Hi,
> I have this problem:
> When I create a new Login with a "SQL server authentication".
> And if I change some User Mapping and Server Roles it gives me the follow
> message "Create failed for User 'win2kadmin "
> Server Name: SERVER\SERVER
> Error Number: 15023
> Severity: 16
> State: 1
> Line Number: 1
> I will be gratful if you can help me,
> --
> Thanks ,
> Peter