Unable to view entire image created from VP Raster File in Acrobat XI Pro

We use software called VP Raster which allows us to edit Raster images, such as TIF or PDF formats within AutoCAD.

We then save these files to PDF format for attaching to our document management system.

In the last couple of days, I am unable to view these correctly within Adobe Acrobat. I was on version 11.0.14 and now updated to 11.0.15. I can view the CAD edits which have been made, but not the raster part of the image.

All of my co-workers are able to view the full PDF, and I can view the full PDF if I use Reader, not Acrobat.

Other users on the same version (11.0.15) are able to view the full file.

Can anyone think of any reason why I have suddenly started to see only part of a PDF and not the whole thing?

I'm stumped!

Apologies if this is the wrong forum - I wasn't sure where to post this.

Many Thanks.