Sounds like this issue:
This is one of many acknowledged bugs that can be found in the Known Bug List here in the Report an Issue section of the forum.
It can also be downloaded as a database file from: http://www.4shared.com/file/8orL8apk/FMP_Bugs.html
Just wondering if you fixed your issue as I am having a similar one.
I did figure out the problem, and it was a silly one. The machine had filemaker server still installed from some time ago. As a result the instance of FMP was unable to share its file out remotely.