Upgrade 5.13.0 to 5.18.0 not working

When I try to upgrade a project that is currently at version 5.13.0 to 5.18.0 I get the following message when trying to open the project in 5.18.0: The project located at [cut] cannot be opened, because the version of the original project file is not supported by this Modeler. Please commit the project first using the Modeler that you last opened it with. I did the following: - Made sure everything is committed - Created a new branch - Opened the branch in version 5.13.0. Made a small change, and committed. - Try to open the branch in 5.18.0. Both when I try to open from disk and when i try to open from Team Server, I get the error message shown above. Does anyone have any idea what's causing this message? In the past, a trial conversion to 5.16.1 has worked fine in this way for this same project.
1 answers

https://forum.mendix.com/questions/7153/Convert%20projects%20to%205.9%20/%205.10%20doens't%20work:%20project%20file%20not%20supported provided the way of finding the actual error. This seems to be a Mendix bug, that may or may not have something to do with XML mappings in our project. Since we have loads of these I am not going to try what happens when I remove them all. I have submitted a support ticket.