We experienced the exact same issue when entering EDX tasks. We recently converted our Data Warehouse Update program over to use EDX calls. We set up approximately 200 EDX tasks. Every 10 - 20 tasks, we would have to restart all QV services as QEMC would become unstable. It was very frustrating and time consuming. It appeared that as we entered more tasks, QEMC became slower and slower until we finally restarted the services. The "Processing...please wait" message became my enemy very fast.
I have reported this (last week) to QV as a bug, but would be interested if anyone else is seeing this issue.
I will forward this thread to the QV Support Tech that I am working with.
We are still researching this, but based on the error in the log, QV support sent us this reply:
I found a few cases having the same error:
Error Failed to create workorder: System.Collections.Generic.KeyNotFoundException: The given key was not present in the dictionary.
Here is what these customers ended up doing to resolve their issue by re-registering .Net Framework.
Reinstall the .NET framework via http://support.microsoft.com/kb/908077 and restart the Qlikview services (Start -> Run -> services.msc). If you can, restart all QV services, not just QVS Service. If your running IIS, restart IIS after restarting the QV services.