Here is another procedure

1- Stop MSSQL Server Service

2- Copy all system datafiles to a new folder

3- rebuild your master database, at this point you'll get access to SQL Server with sysadmin rights

4- Start MSSQL Server Service

5- attach old master database, the one backed up on step 2, using the name master_old

6- Execute the foloowing procedure on master_old databases

http://support.microsoft.com/kb/246133/en-usYou

you will get an script with all the logins in the server with the same sid and password ecrypted.

7- Execute The script from step 6.

8- Attach all users databases

9- set the right default database to every single login.

10- set the rights server roles for every single login.

11- detach master_old database

12- stop mssqlserver service and replaces the datafiles for msdb db with the ones backed up in step 2

13- start mssqlserver service

14- check that everything it's ok, and do a full backup, and also store in a secure place the new credentials for sa

Sorry for my poor english and good luck

Francisco Valdebenito