After migrating a SharePoint site to a new collection; which utilised a globally reusable SPD workflow, I of course expected that the workflow would not be available to the migrated sub site until I published an update. What I didn’t expect though was that updating the workflow would break it everywhere.
First of all I tried updating the workflow settings on the content type (in this case Document) to cascade the workflow settings down to all child content types (including those in the migrated sub site). This got me one step closer to my goal as the workflow then appeared associated with documents in the sub site, BUT once I tried to start a workflow, I got a big fat error: User cannot be found.
So next I opened SPD and updated the workflow and republished it (globally). That all worked and so I tested the workflow in the sub site again- User cannot be found.
So next came Google. I found plenty of people reporting the issue and many of those also bagged Microsoft for telling them that it could be fixed by simply re-publishing the workflow. Since I’d already tried that, I sympathised with their frustration.
Finally, with the magic of Google, I found this post which gave me the right answer. I logged in as an SCA and deactivated and then activated the site collection workflow feature and then started a workflow in my sub site.. Success!