Property IsLocked is not available

I'm running Vista Ultimate x64 and when I tried to connect to my 2005 database using SQL server authentication it gave me an error. When I went to the management studio to check on the login it said this:

TITLE: Microsoft SQL Server Management Studio

Cannot show requested dialog.

ADDITIONAL INFORMATION:

Cannot show requested dialog. (SqlMgmt)

Property IsLocked is not available for Login '[sa]'. This property may not exist for this object, or may not be retrievable due to insufficient access rights. (Microsoft.SqlServer.Smo)

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&ProdVer=9.00.3042.00&EvtSrc=Microsoft.SqlServer.Management.Smo.ExceptionTemplates.PropertyCannotBeRetrievedExceptionText&EvtID=IsLocked&LinkId=20476

BUTTONS:

OK

Has anyone ever seen this before and know how to solve it?

What build is the server running, and what build is your workstation running?|||Product: Microsoft SQL Server Developer Edition (64-bit)
Operating System: Microsoft Windows NT 6.0 (6000)
Version: 9.00.3054.00

|||Anybody?

I know others are having this problem. I've seen it on a couple of message boards.
|||

I ran into the same issue today when I installed an instance of SQL 2005 using Windows Auth. mode. After the install I switched the server over to SQL and Windows Auth mode and ran into the 'sa' problem. I ran the following command and then could see the properties of 'sa' within mgmt studio.

alter login sa

with password = 'yourpwd' unlock,

check_policy = off,

check_expiration = off

|||Works great... Except now I still can't log in with the sa account that I just unlocked from any machine.

TITLE: Connect to Server

Cannot connect to ANGEL.

ADDITIONAL INFORMATION:

Cannot open user default database. Login failed.
Login failed for user 'sa'. (Microsoft SQL Server, Error: 4064)

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&EvtSrc=MSSQLServer&EvtID=4064&LinkId=20476

BUTTONS:

OK

|||You need to change the default database of the sa login. It should always be set to master to avoide this problem.