Sql-server – SQL Server 2008 remote logins fail, local succeeds, remote logins enabled

If SQL Server is started in single-user mode, any user who has membership in the BUILTIN\Administrators group can connect to SQL Server as a SQL Server administrator. The user can connect regardless of whether the BUILTIN\Administrators group has been granted a server login that is provisioned in the SYSADMIN fixed server role. This behavior is by design. This behavior is intended to be used for data recovery scenarios.

So if you have access as an administrator to the machine, you can still access SQL Server - but single-user mode will be required.

Hope this helps.

Raj

Check with your CoLo provider, they may be blocking access to port 1433. Many CoLos started doing this after the SQL Slammer went around a while back.

It's also recommended that you not try and access SQL Server's directly over the internet. Instead setup a VPN between the CoLo and your office and access the servers over this secure connection instead of over the public internet.