Clear the database address, login name, and password that SQL Server 2008 remembers

Log on to the database information on the server, and chose to remember the password, because the server database is used by many people, it is necessary to delete information

Navigate to Filec:\users\%username%\appdata\roaming\microsoft\microsoft SQL server\100\tools\shell\ SqlStudio.bin, make sure that SQL Server is closed , remove the SqlStudio.bin, and then reopen it to completely clear the database address, login name, and password.

 sql Server Management Studio Delete the file C:\Users\%username%\AppData\ Roaming\microsoft\sql server Management studio\14.0\sqlstudio.binsql server Management Studio Delete the file C:\Use Rs\%username%\appdata\roaming\microsoft\sql server Management studio\13.0\sqlstudio.binsql server Management Studio Delete the file C:\Users\%username%\AppData\Roaming\Microsoft\SQL Server Management studio\12.0\sqlstudio.binsql Server Management Studio-delete the file C:\Users\%username%\AppData\Roaming\Microsoft\SQL Server Management Studio \11.0\sqlstudio.binsql Server Management Studio Delete the filec:\users\%username%\appdata\roaming\microsoft\  Microsoft SQL server\100\tools\shell\sqlstudio.binsql Server Management Studio 2005 Delete the File–same as above answer But the Vista path. C:\Users\%username%\AppData\Roaming\Microsoft\Microsoft SQL server\90\tools\shell\mru.dat  

Reference:
How to remove cached server names from the Connect to Server dialog
Removing the remembered login and password list in SQL Server Management Studio

Clear the database address, login name, and password that SQL Server 2008 remembers