NAV11 64bit on windows 2008 64 bit messes up our login to an application with SQL back end

First time on this forum.

After installing NAV11, our custom built application will give us a "username/password" incorrect when we try to log in, we hit OK and then we hit OK again and it lets us in. This is happening on every server we installed NAV11 over the weekend. Once we remove NAV11 the issue goes away. The login to our app is using our Domain credentials.

Any help would be appreciated.

First time on this forum.

After installing NAV11, our custom built application will give us a "username/password" incorrect when we try to log in, we hit OK and then we hit OK again and it lets us in. This is happening on every server we installed NAV11 over the weekend. Once we remove NAV11 the issue goes away. The login to our app is using our Domain credentials.

Any help would be appreciated.