I came accross this problem trying to recieve files on remote servers using the file adpter: "File transport does not have read/write privileges for receive location 'G:\if067\outbox\'". I read there:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/troubleshooting/htm/ebiz_prog_adapt_owtd.asp
that you need to map a network drive to the recieve location and specifiy the user name and password that has access rights to this share. So I did, and you can see it in the error message I get in the event viewer. The recieve host runs under the same account I used. To test I logged on with this user and sure enough, I have full access and can read, write, modify and delete files on the share. A good collegue of mine (who always helps me out with infrastructure issue might I add) mentioned that the shared drive is flaky and I would be better off sticking with the UNC (e.g. \\servername\share name) instead of the G:\ mapped drive. He also suggested using Filemon to find out what is going on. So now I can't wait till Monday to solve this! So far I can't read, or write to the remote share.