Upgrading to Namespaces forces to resave all page types in CMS

Silverstripe Version:

I have upgrading my silverstripe website from 2.x to 4.1. Now i run into the problem that the pagetypes in the CMS do no exist anymore because of introducing NameSpaces and therefore i have to resave all the pages in the CMS. After this the pages work fine again and the data is there.

The .upgrade.yml provides a mapping between the old class and the new namespaced class, so i would i assume this takes care of that problem. But i cannot find/see the use case of this .upgrade.yml file as these mappings clearly do not work.

Does anybody have a solution for this? or could point me to the documentation that i missed? i followed the official upgrade documentation and used the CLI to do the namespacing.

Thanks in advance

I know this is a late response, and I don’t know if you managed to fix it. But I ran into this thread - which solved it for me. I had this happening with one page type, and funnily enough, it was the only page type NOT in my legacy.yml file. Try adding all the mappings there to solve your problem.