Hi Raj,
The error you are receiving indicates that the login failed for the SQL Server instance.
Has the sa password changed since installing the server components on the server?
Can you try running the following on your SQL Server?
EXECUTE master..sp_addextendedproc sqbsetlogin, 'xp_sqlbackup.dll'
EXECUTE master..sqbsetlogin 'sa', 'yourpassword'
EXECUTE master..sp_dropextendedproc sqbsetlogin
http://documentation.red-gate.com/display/SBU7/SQL+Server+error+18456+-+login+failed+for+user#
The error you are receiving indicates that the login failed for the SQL Server instance.
Has the sa password changed since installing the server components on the server?
Can you try running the following on your SQL Server?
EXECUTE master..sp_addextendedproc sqbsetlogin, 'xp_sqlbackup.dll'
EXECUTE master..sqbsetlogin 'sa', 'yourpassword'
EXECUTE master..sp_dropextendedproc sqbsetlogin
http://documentation.red-gate.com/display/SBU7/SQL+Server+error+18456+-+login+failed+for+user#