You may be unable to connect (using TCP) to a SQL 2005 instance if you have Venturi Wireless Software Installed

I recently came across a situation where If you are trying to use TCP connectivity to connect to a SQL Server 2005 instance, it may fail with "login timeout failure". This is despite the fact that SQLBrowser is running and binding the 1434 port correctly. If you use TCP alias, the connectivity worked fine suggesting that TCP discovery of instances is failing.

Cause that we found:
A DLL from Venturi Wireless software - vlsp.dll - was getting loaded inside SQLBrowser process space that was blocking the browser’s response to the UDP requests.

Resolution that worked:
* Collected a memory dump of the SQLBrowser by using SQLDumper by following:;EN-US;917825

* Analysis of the dump showed that vlsp.dll - is getting loaded into the SQLBrowser process space.

* We uninstalled the Venturi Wireless and VZ Access Manager software from this box and connectivity started working fine. We confirmed that local and remote connectivity and portqry instance enumeration works fine after this.

* In such situations, please try to uninstall/disable Anti-Virus Softwares, Network Monitoring and the dial-up or VPN connectivity software that may have been installed by the ISP.

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