Exception at uno.util.Bootstrap.bootstrap()

After installation of lo 5.0, my application written in C# running on Win7 does not work anymore. The bootsrap call delivers an exceptio: “System.Runtime.InteropServices.SEHException”.
I have read somewhere that the reason is that the URE folder does not exist anymore in lo 5.0.
I have used the new dlls and have tried other things, but I am not able to fix the problem.
Any hel?