FMP 9 for Mac cannot open PC attachments

[olouie]

I am a complete newbie to FMP, but at work we have a new setup where some of us are on Macs and some on PCs. The person who I am working with is using a PC and I use both PC/MAC.

Whenever anyone attaches a .pdf file using a PC, the mac users cannot open the file (cannot double click or extract it to desktop etc). PC uses seem to be able to open their own attachments and those attached using a MAC.

Does anyone have any advice about how to fix this problem?

Thanks in advance.