There is a similar year-old question with no accepted answer, so I though I would post this one with more detailed information.
I created some 2010 and 2013 workflows using SharePoint Designer 2013 on my office computer (My company is using SP Office 365). They work just fine. I can open and edit them as I please on Designer.
A co-worker is collaborating on the project and needs to be able to open and edit the workflows on he's own computer. When he opens the 2013 workflows and clicks on
"Edit Workflow" he finds an empty workflow. But when he opens an 2010 workflow he can edit it just fine.
He created some 2013 workflows of his own and I was able to edit his workflows on my computer. So its not a two-way problem. The workflows I create cant be edited by anyone except me. We checked with a third co-worker and she cant edit my 2013 workflows neither, but 2010 are fine.
Does anyone have a clue where the source of the problem is? I could not find a solution anywhere on the web. I'm curious to see if anyone can replicate this problem.