It suggests the file is corrupt.
An easy, non techy (but also not guaranteed) way to tell is to compress the file and see how much smaller the file is when compressed. This is NOT an exact science but, for example, if you had a 2gb file and it compressed to 2kb then this is a good indication.
In your case, since the .rpt file is 690kb but compresses to 56kb (approx 8%) it suggests there is nothing you can do (unless a tool exists to recover .rpt files).