Previous updates disappear after new updates

[TSallay]

I share Robohelp with another user storing our completed files on a share drive.  My license is Robohelp 2017 na d the other user has Robohelp 2015.  When either of us submit updates, the other user's previous updates disappear.  Previoulsy this arrangement worked fine when both users had Robohelp 2015.  Do both user have to use the same version of Robohelp or is there something else that may cause this to happen?  Thank you   

[Jeff_Coatsworth]

You defnitely need to be using the same version if you're swapping projects back and forth. I don't recall RH having any ability to back-save to older versions, so even that wouldn't work.

[Amebr]

It  *might* work if you use only the most basic features and make sure you delete the .cpd file before you open the project. In a previous job (using the same version) we deleted this file if we had to work on a project that someone else had worked on. There's definitely a setting in RH2017 to automatically delete it (something like Clear the project cache on open) but I can't remember if that setting exists in RH2015.

But I feel like there were some fundamental changes in RH017 so I'd  really recommend that you're on the same version.