Corrupt documents after switchover to Acrobat X Standard from Acrobat 5

Question

At this workplace, we have had Acrobat 5 Standard copying and pasting pages from any PDF file from suppliers, Lanier printer / scanner units, AutoCAD.
We have now moved to Acrobat 10 Standard, with latest updates.
Aribitrarily people have been opening the odd existing PDF file and added some pages and saved with Acrobat 10 Standard.
On re-open we have encountered file corruption behaviour - using Acrobat 10 Standard and Acrobat 10 Viewer, we are seeing one or two thumbnails as blank.
I've tried googling for recovery tools and have worked through oh, 5 or so - in short, they are not able to do anything worthwhile  - first page only or did not complete the process.
My most successful attempts are:
1. Sumatra PDF - it can see 95 out of 100 pages (the last pages are blank) which is impressive
2. FoxitPDF Reader - similar
3. PDF XChange - similar
Writing out a clean PDF of 95 pages is another task.
My Questions:
1. Why does the odd PDF corrupt? It does not happen everytime when Acrobat X Standard re-edits the existing old pdf files?
2. How can we resolve this issue?
3. What is the most effective repair utility if there is one better than the others?
Thanks
Ananda

Answer 1

Hi Bill,
Good idea about Save As. I myself often save versions of Excel and Word documents as I work but this workplace here doesn't do that for their PDF documents. It is a good idea, increases the files but they have enough network server space (Microsoft Servers). They enclose all kinds of pages into a one document so that they can keep track of the entity - no IT reason why they can't adopt a safer practice in the interim until this is sorted out.
The source files could come from email, scanner, AUTOCAD. However, their issue is that the single destination file was originally ok, the new incoming files are originally ok and when they insert pages into the good destination file using pages from good incoming files, they end up with pdf corruption after save and re-open.
They are not worried about backward compatibility - they now have all Adobe Acrobat Standard 10.
Will batch file conversion help in any way? That is, process all these files to Acrobat 10 level, then use Acrobat 10 normally?
How do they do batch file conversion - can they do that with Acrobat 10 Standard?
Thanks anyone for your help
Ananda