>>>>Hi,
>>>>
>>>>I have a client who has SQL Server express 2008 R2 installed. We created a database on it and our software runs against this database fine. I need to do some maintenance to it now but cannot get access to the database. The Object Explorer connects fine, but I get messages like:
>>>>
>>>>"The database is not accessible. (ObjectExplorer)"
>>>>
>>>>They don't know the sa password.
>>>>
>>>>One thing I've noticed is that they apparently have SQL Server 2012 installed (which wasn't there last time).
>>>>
>>>>Any ideas what I can do?
>>>
>>>You application runs fine, isn't it?
>>>If so, just use the same account you use in your application when you connect with SSMS.
>>
>>I believe the application uses Windows Authentication so I am not sure if I can log on at their server using one of the users rights. Their IT people are trying something out right now so I'll have to wait and see.
>
>Install SSMS on the computer where your application is installed and login from there :-)

Good idea. Someone else pointed me to this:

http://blogs.msdn.com/b/raulga/archive/2007/07/12/disaster-recovery-what-to-do-when-the-sa-account-password-is-lost-in-sql-server-2005.aspx

which should help too.