SQL Server wants to open properties of wrong database and cannot restore logs of different databases at the same time

We have implemented our own way of logshipping by backing up the transaction logs of all our non-system databases every hour. Then we transfer the backups (before SQL Server 2008 R2 with additional zip and unzip steps) to the second environment where we restore them only during the night on databases in standby-state (Like this, our developers can access the databases without disturbing the productive system and we can restore the t-logs during night, so not shutting out the developers during the day).

Now since we replaced our hardware in the productive environment, we replaced the hardware in the second environment with the servers from previous productive environment. Same SQL Server 2008 R2, same Service Pack (SP2), same installation procedure. But since then the SQL Server in the second environment behaves different:

- When the logs of some database "A" are restored, I cannot access the properties of any database, i.e. database "B", I only get the error message "Cannot show requested dialog. (SqlMgmt) Database 'A' cannot be opened. It is in the middle of a restore. (Microsoft SQL Server, Error: 927)"

- Our logshipping runs multiple instance at the same time, so restoring multiple databases' logs. But since the change, two of the instances fail restoring of datatbases, i.e. "B" and "C" with the error message "Database 'A' cannot be opened. It is in the middle of a restore.". The jobs guarantee to restore only logs of the database they need to restore, they have strictly separated sets of target databases and only try to restore the databases of their sets.

Before the new installations, we did not have these strange behaviours. But as said, it is the same SQL Server version, the same service pack, and we followed the same installation document but maybe with the small changes in settings. The user the jobs are running under is a domain admin, the login they use has dbcreator, processadmin, db_owner and db_backupoperator roles. My login on the SQL Server has sysadmin rights and as described similar problems.

Is this problem known or does somebody have an idea where to go looking for?

Thanks, Chris