Workflow 3.5 and MOSS 2007 - This task is currently locked by a running workflow and cannot be edited.

Morning,


Today I had an interesting issue with my WF3.5 SharePoint workflow.
A user was attempting to action a SharePoint workflow task and was given the error:


This task is currently locked by a running workflow and cannot be edited.

I have seen this error a small number of times (5-10) amongst the 1000's of workflow instances that have passed through my production system.


I am always very careful with quiescing and always release a new workflow version the correct was using workflow.xml, feature.xml and stsadm.


There was a time a few weeks ago when we had to do an emergency bug fix as some of my business logic was not functioning as expected.


I know that I can never change an activity in my workflow without quiescing otherwise the serialization and deserialization (dyhydrate / re-hydrate) from the persistence store gets confused and hence an error like this occurs.


The funny thing is, I only changed code in a utility class and only the code inside an existing method (ie...method definition was not changed) so I thought that there was no need for quiescing. (no core workflow code was altered).


Anyway,just writing here incase anyone has an opinion on this. 


From now on I will quiesce no matter what the emergency is!!


RuSs