I cant open any document Project
Now I can't open any document created by project. The document in gantter doesnt shows information.
Which version of Gantter are you using?
Are you trying to open a Gantter file from Google Drive or by opening the file from within Gantter itself?
If you are trying to open the file from Google Drive by double-clicking on the file then you might be seeing a screen that says "No Preview Available", try instead to open the file by right-clicking the file in Google Drive and choosing "Open with".