"Could not read item data"

[vege_san]

I seem to be having a random problem with opening my Game.rxproj
I had no problems opening it before, then after not working on it for a week or so I try to open it again and I get the error message "Could not read item data" im not sure how to exactly fix this problem and I really cant afford to lose all this progress I've made in making this project >_< I can't even test play or else I get this message "?? 'Scene_Title'21 TypeError??? incompatible marshal file format (can't be read) format verison 4.8 required; 0.0 given" PLEASE HELP, it would be GREATLY appreciated thanks in advance!

[Me™]

Your Items.rxdata in your Data Folder is corrupt. Create a new project, go to the directory of the folder, and copy items.rxdata from that directory to your data directory. Pres yes when it asks you to overwrite.