I have two Task lists: "Recurring Tasks" and "Task Queue". Recurring Tasks contains tasks that we have to do every day or every week and do not want to have to manually recreate the same task again in the queue.
I have a workflow called "Send to Queue" in the Recurring Tasks list, that does the following:
If Current Item:Workflow Helper Field equals "Activate Workflow" log Starting Workflow to the workflow history list then set Workflow Helper Field to "Workflow in Progress" then create item in Task Queue (Output to Variable:Create) then log Created Task [%Variable:Create%] in Task Queue to the workflow history list then Pause for 0 days, 0 hours, 1 minutes then log Finishing Workflow to the workflow history list then set Workflow Helper Field to Ready Else log Workflow Helper Field is [%Current Item:Workflow Helper Field%], no action taken. to the workflow history list
The workflow is set to run on item changed. It's set up this way so that we can go to the Recurring Tasks list, filter to e.g. show only the weekly items, then go into datasheet mode and quickly set the Workflow Helper Field to "Activate Workflow" on all of the items at once, activating the workflow on all of those items. The Pause step exists because without it, the entire process sometimes completed so quickly that team members sometimes thought it didn't work and did it a second time.
Most of the time, this all works just fine. But occasionally, one or two of the items will have an error in the workflow after resuming from the Pause step. Here's what I see in the workflow history list in that situation:
Date Occurred Event Type User ID Description 2/14/2017 4:29 PM Comment System Account Starting workflow 2/14/2017 4:29 PM Comment System Account Created task 2002 in Task Queue 2/14/2017 4:29 PM Comment System Account Pausing for 1 minutes 2/14/2017 4:30 PM Error System Account An error has occurred in Send to Queue.
At first I thought the problem was related to the last step of setting the Workflow Helper Field back to Ready, but looking at the history entries for a successful workflow I see that they have an entry after the "Pausing" entry that says "Pausing complete", which is missing in these error instances, so it appears that the issue is in the resuming itself.
I've looked at all of the other questions I could find here about workflow pause-related failures, but none match the vague error message "An error has occurred in [workflow name]".
An additional note: sometimes several minutes pass between the "Pausing for 1 minutes" message and the error. I think the longest I've seen was about 7 minutes.
I'm an SCA on the site, but do not have any access to anything on the server side, and do not have the pull to e.g. get a server-configured limit increased.
What is causing this error? Why does it only happen on a very small percentage of the workflows? Can I prevent it?