Recently  I had to downgrade my DNN Pro 7.X instance to Community Edition. Everything  works fine again except for two things relating to HTML/Text Module:

1) When I edit HTML/Text via HTML Editor and press save, the changes are not saved, the editor stays open. Closing the editor manually is possible, but ofcourse without update

2) When i edit HTML/Text via inline Editor,i can edit the test, press the save button and it appears that text changes are actually made. However, when i refresh the page, the changes are gone again.

I suspect that the two issues have to do with each other. It looks like a cache issue in relation to HTML/Text editor (which is not unlikely since caching between Pro and Comm is different). All other existing modules work fine.

I have updated/removed all entries in web.config that refered to the Professional edition settings. I have deleted all professional modules and upgraded HTML/Text Community module to the most recent one. I have upgraded HTML Editor to the latest CK Editor, i have changed HTML Editor settings accordingly. I have compared web.config of another community instance with the downgraded Pro instance (i.e. to see difference in cache setting). I browsed through ISS 7 settings to see if there is any caching. I have deleted the cache files on the server in portals/6/cache directory). I have removed all Pro files in Bin directory.

I'm running out of ideas. On none of the portals people can edit text/html which is really bad. Does anybody have suggestions on where to look next?