Redundancy - error by loading from ES to OS

Hello,

Im using an Engineerstation (ES) with Step7 v5.4/SP3/HF1 and WinCC v6.2SP2.
In that project I have 2 PC-stations: one as wincc-apllication (OSMaster) and one as WinCC-apllication stby (OSMaster_StBy). When I try to download it for the first time to the 2 serveurs (so inan empty folder) everything goes fine.

Then I start WinCC on both servers and deactivate them and close the projects.
Then I try again to download the project to the two servers and get an error:

Display load log...
-------------------

2/04/2008 13:13:12 : The project was locked.
2/04/2008 13:13:12 : The entire WinCC project will be transferred to the runtime OS.
2/04/2008 13:13:12 : The path of the Runtime OS is indicated for the redundant partner.
2/04/2008 13:13:12 : The target directory is read-/writeable.
2/04/2008 13:13:12 : No project is open.
2/04/2008 13:13:24 : The WinCC project is being closed
2/04/2008 13:13:25 : The project was locked.
2/04/2008 13:13:39 : Caution: An error occured while changing the computer name in project SERVEUR2.
2/04/2008 13:13:39 : The lock on the project was removed.
2/04/2008 13:13:39 : Caution: Downloading the OS failed. Duration: 00:00:27

I can also see in the project folder on the server that there is a file ProjectOpened.lck

What can be the problem. When i delete the complete folder (by STOPPING SQL-server2005) I can download again one time.

Any suggestions are welcome.

best regards,

Bart Kumbruck