Hello,

we have a custom list where every month the users have to input their current odometer readings for their electric cars. To make this as comfortable as possible for the users, we send them a request data task. All this happens via a scheduled site workflow which runs every month. This workflow and also the list exist for a long time. However, since yesterday some of the workflow instances fail after the user commits the input.

How does the workflow work:

The workflow starts every month and sends each driver their personal task. To make this happen the workflow queries every driver and in a for-each loop a task will be sent (the task uses a custom content type with a number input). Then the column "WF running" will be set to yes and the workflow starts itself again - so this is kind of a recursive way. After all that is finished, around 130 instances are running.

How does the error look:

After the users input their new odometer readings and finish the task, some of the workflows fail with: Error in "name of the workflow".

So my problem is not very consistent because since yesterday approximatly only 1/4 of the instances fail. I would realy appriciate if someone has a good idea on what is going on here. Since the workflow is not failing during the update of the odometer column but rather after the user input, I thought about problems with the timer service (maybe only on one of the SP servers)? Am I hitting some, at least for me, unknown boundaries with that many instances?

If you need more information than please ask.