Hi,

after upgrading from 2.6 to 2.7.3 we are having are getting data corruption when opening pdfs that where saved with 2.6. Somehow the pdf gets altered so that embedded fonts can't be rendered anymore. When saving & reading with the same version (tried with both 2.6 and 2.7.3) everything works fine.

I have attached an intact and a corrupt file. The corrupt file doesn't display properly in Adobe Acrobat (you will also get an error message there) and DiffPdf will find visual differences (text that is using embedded fonts isn't rendered). It will display properly in Chrome though. The intact file displays fine everywhere. The difference is visible on the first page on the line starting with '1.1'.

DiffPdf doesn't find a difference in the files using word by word comparison. There are some minor binary differences though. E.g. in the first line there are some additional characters (see attached WinMerge screenshot).

In case this is relevant: During my research I stumbled upon a thread where someone described the same problem in pdfs. As it turned out he was uploading pdfs via ftp in ascii mode. Switching to binary uploads solved the problem for him. http://www.macuser.de/forum/f17/eingebettete-schrift-konnte-352152/

Let me know if you need any more info. As for the priority - this isn't a blocker for us because only a hand full of files on our production server are affected by this issue.

Cheers,
Andi