[RESOLVED] Winform Application with multiple users

Not sure if this is the right area, sorry if it's not.
I have a winform application (vs2010) which is using sql server 2008 express. I now find out that multiple users will need to use it. I have sql server loaded the computers and computer A is where the database will be stored and computer b and c will need to access that data over the network. My workplace doesn't want to load sql on the server because only these three computers need to use this program and data. I thought all I would have to do is change the connection string on computer b and c to attach to computer A's server, but when I load the form with parent/child relationships I get the following error: Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign-key constraints. If I choose to continue it loads up the form just fine with all the data. I know that the tables are fine as far as the constraints because it will load up just fine on computer A (without the error) where the database is located. The datatables fill in the correct order to prevent constraints so not sure why I get this error on b and c. I am able to connect to the sql server on computer b and c through management studio and I can select and edit the tables just fine. I can even go into the server explorer in VS2010 and show table data on the tables. Am I missing something, do I need to set something up differently now that multiple users will be using the program.

I am thinking of running the programs on each computer and then having them tie into the same sql server database on computer A. Does that sound plasible? I am new to vb.net, visual studio and sql so any advise you can give would be most appreciated.

Thanks,
Stacy

P.S. Computer A is Win7 x64 and Computer B and C are WinXP x86 if that makes a difference.