Hi all, Just found this, apparently a bug, in BoostJam. I'm using an admittedly old version of Boost, V1.36.0, in this particular instance. I'm using the latest BoostJam, V3.1.17. This occurs on Windows when the TMP environment variable contains spaces. In my case it was "C:\Documents and Settings\xxxxxxxxxxx\Local Settings\Temp" When you try to run something like C:\Programs\Win32\BoostJam\V3.1.17\bjam.exe --build-type=complete --toolset=msvc-90 --with-thread You get MkDir1-quick-fix-for-windows bin.v2\libs\thread 'C:\Documents' is not recognized as an internal or external command, operable program or batch file. if not exist "bin.v2\libs\thread\\" mkdir "bin.v2\libs\thread" ...failed MkDir1-quick-fix-for-windows bin.v2\libs\thread... This is fixed by set TMP=C:\temp I don't know if this merits a patch. Regards, Paul Paul Bilokon, Vice President Citigroup | FX - Options Trading | Quants 33 Canada Square | Canary Wharf | Floor 3 London, E14 5LB Phone: +44 20 798-62191 paul.bilokon@citi.com<mailto:paul.bilokon@citi.com>