Checkin doesn't work!

Hi,

I'm using RSC 3.1 to work on a Robohelp 8.0 project. Uploading the project works fine. Check outs als no problem, but when changing topics on local client I can't check in them back. I get the following message:

Der Wert darf nicht NULL sein.

Parametername: path1

Server stack trace:

bei System.IO.Path.Combine(String path1, String path2)

bei NG3Server.NG3DAL.AddFileHelper(String path, Stream str, Object trns)

bei NG3Server.NG3Database.CheckIn(NG3Connection conn, String path, Byte[] _CommentAndDetails, UInt32 CheckOutID, OptimisedStream Contents, Int32 nNewVersion, DateTime explicitDate, BranchRef branchRef)

bei NG3Server.NG3Server.CheckIn(Int32 ConnID, String path, Byte[] commentAndDetails, UInt32 checkoutID, OptimisedStream Contents, Int32 nNewVersion, DateTime explicitDate, BranchRef branchRef)

bei System.Runtime.Remoting.Messaging.StackBuilderSink._PrivateProcessMessage(IntPtr md, Object[] args, Object server, Int32 methodPtr, Boolean fExecuteInContext, Object[]& outArgs)

bei System.Runtime.Remoting.Messaging.StackBuilderSink.PrivateProcessMessage(RuntimeMethodHandle md, Object[] args, Object server, Int32 methodPtr, Boolean fExecuteInContext, Object[]& outArgs)

bei System.Runtime.Remoting.Messaging.StackBuilderSink.SyncProcessMessage(IMessage msg, Int32 methodPtr, Boolean fExecuteInContext)

Exception rethrown at [0]:

bei System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)

bei System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)

bei NG3.Core.IServerInterface.CheckIn(Int32 ConnID, String Path, Byte[] CommentAndDetails, UInt32 checkoutID, OptimisedStream Contents, Int32 nNewVersion, DateTime explicitDate, BranchRef branchRef)

bei NG3.MiddleTier.NG3MiddleTierDatabase.CheckIn(NG3MiddleTierSession session, NG3MiddleTierNode node, String Comment, String LocalPath, RecursiveOption recurseOption, CheckInOption option, DateTime optionalCheckinDate, BranchRef branchRef)

bei SCCAPI.SCCIMPL.SccCheckin(Int32 context, Int32 hwnd, String[] fileNames, String comment, SccCheckinFlags flags, Int32 options)

Please help!