I've created some long running timeout-workflows which waits for a specific
amount of time after an update is done to my users entity, and then send's
an email to notify the user.
If I unpublish the workflow, makes changes, and publishes it again then the
old instances of the workflow continues running the old workflow, and new
one's are using the new workflow. That is ok, I guess.
My problem is that sometimes the old version of the workflow crashes and
sometimes it is running fine. I've found no reason why it crashes and the
error message only tells me to contact Microsoft.
A possible workaround is to cancel the running instances of a workflow
before changing them and then manually start them again after publishing the
new version. This is a lot of work, so I hope there is another way.