Mobile Broadband software can cause LANSA communications and Debugger to fail

Date: 30 May 2011
Product/Release: Visual LANSA
Abstract: Some Mobile Broadband (wireless data dongle) software can make changes to the TCP/IP stack, causing problems with the LANSA listener and VL debugger.
Submitted By: LANSA Technical Support


An issue has been found on some notebooks where the VL debugger does not stop at the requested breakpoint. Further investigations found that the listener on those PCs could not accept incoming connections either.

The issue has been traced back to a change in the TCP/IP stack made by software used for Mobile Broadband data sticks (also called 3G Data dongles, depending on your location). When installing the software for these data devices, often ByteMobile Client software is installed alongside the main connection software.

ByteMobile Client is used to compress data to speed up communications. It does this by adding a Layered Service Provider DLL (bmnet.dll) into the TCP/IP stack, which is then used by all internet communications. However in this case it affects the LANSA Listener/Debugger.


This issue is related to a previous technical note 3rd party software causes LCOTP.exe to fail. The technical information in that note is still valid, and we still recommend the use of this tool to detect/remove unwanted entries from the communications stack. However, if security policies prevent you from installing third party software, the recommendation is to uninstall the ByteMobile Client software on PCs that have Visual LANSA installed and require debugging functionality.