Saved file problem

when i save a project  almmost 7 files are created including the html file and the.ae file...but when i open th .ae,the ege animate opens but in the work space only a white screen shows up..every layers  i've used is gone, in short "EVERYTHING IS GONE"... i've tried reinstalling the software several  times .still no use

NOTE:some times when i open the project through "recent file"  it works