Access 2007 Adding a trusted location on a network drive

I am using an XP machine with Access 2007.  I created a database and put in in a folder located on an XP box.  I shared the folder on the network as a hidden share and added me with FULL CONTROL on the security tab.  I tried to add the location as a trusted location in the trust center and it gives me this error:

"The path you have entered cannot be used as a trusted location for security reasons.  Choose another location or a specific folder."

I have tried lowering my security settings in IE on "Local Sites' on the security tab but I do not believe it is that kind of issue.  I also have tried the check box:

"Allow trusted locations on my network"

both checked and unchecked.  I have tried mapping it in the trust center with IP (i.e. \\10.10.2.25\Share\sharesub) and by mapped drive (i.e. U:\Sharesub).  It gives me the same error every time.  How can I get this location to be a trusted site?