SQL Server 2008 ODBC and Access

I am linking an Access database to SQL Server 2008 using ODBC. I use the 2008 drivers and I can set up the link and it tests fine. In the database I can open the tables and edit/view the table's data. When I open a form I get an error:
Connection failed:
SQL State: '08001'
SQL Server Error: 10061
[Microsoft][SQL Server Native Client 10.0]TCP Provider: No connection could be made because the target machine actively refused it.
If I click ok and then ok on the next SQL Server Login popup (Using trusted connection) it will display the form and the data.
Any ideas? I have made sure the allow remote connections was enabled and also tried different protocols.

do you use named instance?
run sql browser.

Thank you for your responses.
The server I am using is the same machine I use for development. So, I tried all the protocols as well as trying each as the only one enabled. I am not sure why this worked, but I relinked all the tables in the Access application and that has solved the problem. I upgraded the server and the ODBC drivers, but when I did this is did something to the links in the database. I am not sure why.

It is supposed as you linked sucessfully the tables , the link continue working.
if you use dynamic port , try to use static port.
let tcp/ip the first protocol using the configuration tool.

I tried that as well. I had to re-link the tables. I do not know why that this had to be done.