sql server - Intermittent ODBC connection failures

Question

We are developing an in-house 32bit app. The app connects to a SQL Server. The test environment is SQL Server 2008 R2, and the live environment is SQL Server 2014 SP2.

Connection to the database is made using this ODBC string:

Driver={SQL Server};Server=<redacted>;Database=<redacted>;Trusted_Connection=Yes;

The users for this database belong to a 'domain local' security group. We have users from three different AD domains as members of this group. The group is defined as a login for the SQL Server and a user for the target database. In the test environment, this worked fine.

In the live environment, only some of the users can successfully connect to the database. Interestingly, users who are in the security group but NOT in the same domain as the server can connect. Users in the same domain as the server cannot. (I've not checked with all 25 users, but that's the pattern I'm seeing). Users (like me) with sysadmin rights to the database server have no trouble.

I've been over everything I can think of with a fine tooth comb trying to figure out why it works on one server but not the other, with no luck. I've tried removing the group as a user & adding back, taking users out of the group and putting them back in, and so forth. The SQL Server service is running under the same domain account on both servers.

Any insight is appreciated.

Answer 1

Thanks to Birel for pointing me in the right direction. The answer was that on the new 2014 server, the 'SQL Server Browser Service' was not running. I set it to automatic startup, and started it. That resolved the issue.