InfoPath Dev

I have an Infopath form which is connecting to an Access DB.  I've got many forms which I can get to work, but nobody else can,  When other people try, they get this message:

The query cannot be run for the following DataObject: Main connection

InfoPath cannot run the specified query.

InfoPath cannot connect to the data source.

InfoPath has encountered an error. The operation failed.

I know these other people can access the database in question so that shouldn't be the issue.  I tried assigning the forms Full Trust and even signed with a cert and installed it on their computers.  The issue has persisted.  Even odder still is that I have several forms which work for myself and my staff.  These forms are using the exact same data connection.  I've even copy/pasted from those forms to the problematic ones with no luck.

 I've scoured the internet and have found nothing.  Help me InfopathDev, you're my only hope.

Are the forms published to SharePoint or are people opening them from a network share. Is the Access DB on a server in the same domain?

The forms and DB are on a network share.  They're in the same folder tree but in different folders.

 Here's an interesting fact.  The forms that work weren't created by me.  They were created by a different user.

I've been working on this with the guy who designed the other forms.  We compared notes and found nothing different in our work processes.  I figured I'd try creating the form from a machine other than my own.  Once I did that, it worked!  I'm on Win 7 and the computer I did the form from was XP.  Does anyone know of any compatibility issues with 7?  I tried to run the forms I created on another Windows 7 computer and they still don't work.  This is odd.  I think I've at least found a solution temporarily.

This rings a bell for me - but I think it was a difference in DB connections when the form was designed in IP 2010 instead of IP 2007 (even though the compatibility was set to IP 2007) - Any difference in IP versions on the different machines?

No difference in IP.  Even if there was I would expect the users with IP 2007 to work fine.  Seems the only difference is the OS.  I'm working on finding out if its a permissions thing but I don't see how that's possible since some forms work and others don't.

Here's another interesting tidbit.  If I was using SQL as I've done on other projects, there are no issues.  It's got to be something with a connection string and/or how my computer interprets it.

 Hopefully other people like me find this post.  There's really nothing out there to tell me why this was happening.

It would be interesting to compare the form files between the two operating systems - the same form with the connection created on XP in one copy and created in 7 for the other copy. Save as source files and use a tool like WinMerge to compare....

Saving as source files creates a bunch of files.  Which files should I compare?

Oh, I'd be looking at manifest.xsf, probably, to start with. Again, you want it to be the same form so you can see if there are any pertinent differences....

A bit more info.  I tried creating these forms from another Win 7 computer and they work fine.  It's got to be something on my machine but I don't know what it could be.  This is frustrating, but at least I know I can work around it.  I've got to try it on my laptop and see if those work.  If they don't then it's a permissions thing that I'll have to sort out.

Thanks to everyone for your help on this.