Hi, I used the boost library installer from boostpro to install the 32 bit version on my system. All projects compile and link fine for the 32 bit target in Visual Studio 2005. But when I switch to the x64 platform target, I get linker errors. So I decided to compile boost myself, with the following command: bjam.exe --build-dir=e:\boost-build --build-type=complete --toolset=msvc --address-model=64 and installed the result in a separate lib_x64 folder in the boost installation from boostpro. All projects with the x64 target add this path to the linker settings. The libs are found, but when I compile the project, I get the following linker errors: http://pastebin.com/saQMtFwX All problems seem to be related to the regex library. I then created a complete new project with a simple source code, just for testing purposes: http://pastebin.com/QyQRiQ5p It compiles fine with the w32 target, but not with the x64 target (libary path has been changed accordingly). Is there any known issue when using regex with x64? Do I have to set some variables first to make this link correctly? Andi -- Neu: GMX De-Mail - Einfach wie E-Mail, sicher wie ein Brief! Jetzt De-Mail-Adresse reservieren: http://portal.gmx.net/de/go/demail