Description: The trial version 13.1 of Statistica has been installed but older files created in Statistica 10 will not open.  The error is "Failed to open document."  

Cause: One possible cause is file corruption when files where transferred from one location to another or one drive to another.  

If the older files were copied from one location to another, delete the corrupted files and then copy the files again.  It may be best copy all files to a folder and then zip up the folder.  Then just copy the zipped folder.
 

Note:    If the source files are corrupt, copying them again will not resolve the issue.