Microsoft SQL connection error with firewall turned on

Posted on 2009-04-28
Last Modified: 2012-05-06
While mobile users are connected at the office with the local firewall turned off through group policy, multiple line of business apps that connect to different SQL 2005 servers work .  Once they leave the local network and connect outside, the firewall (Vista SP1) automatically turns on.  After connecting through a SSL VPN, the line of business apps fail with the following error;

Connection Failed:
SQL Server Error: 53
[Micosoft][ODBC SQL Server Driver][DBNETLIB] ConnectionOpen (Connect()).
Connection failed:
SQL Server Error:17
[Micosoft][ODBC SQL Server Driver][DBNETLIB]SQL Server does not exist or access denied

Allowing TCP/UDP ports 1433 and 1434 on the client do nothing.  If I completely disable the firewall for public networks on the client all the apps work fine.  I  really would rather not do that though.

Any suggestions?


Question by:RomanekT
    LVL 6

    Expert Comment

    I think you have to do both ways:

    *ANY* -> 1433
    1433 -> *ANY*

    What you could also do is enable firewall logging on the client (may need a restart to enable) to spot where traffic is being dropped.


    Author Comment

    Thanks but that article doesn't apply to SQL 2005.  Also, all clients are Vista SP1.  There is no option in the firewall to make rules like ANY->1433, you can either pick an application or create an exception for a port.  
    LVL 6

    Accepted Solution

    You can using the advanced firewall feature in Vista (type advanced firewall in search). Ports should be the same...
    (also be aware of the 3 profiles; public, domain and private)

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