USE THE FOLLOWING TO SEE SYSLOGINS AND PASSWORDS  :

SELECT * FROM MASTER..SYSLOGINS

With NO LOCK ,

IF THERE IS ANY LOCK SUCH AS TAB LOCK OR PAGE LOCK YOU CAN READ SUCH OBJECT.

USE

SELECT * FROM <TABLE NAME> (LOCK HINT)

LOCK HINT :

TAB LOCK

NO LOCK

PAGE...

Theare may be a problem of network?

Be sure that your network cable is connected properly?

USE THIS QUERY :

IN THIS QUERY

MYTAB_DATE IS A TABLE WHICH CONTAINS SQL DEFAULT DATE 

UPDATE MYTB_DATE SET DT=NULL WHERE DT=CONVERT(DATETIME,' ')

you can use the exec command

rather to use sp_executesql.

syntax is

exec (@stmt)