One interesting learning today…  I was building a BizTalk Server machine that was designed to be a production server (production defined to mean no locally installed Visual Studio.Net, no local SQL Server, etc…)  and ran into a problem where BizTalk couldn’t write a .dll file…  After some nashing of teeth, it turns out that the BizTalk installation program requires permissions to the C:WindowsTemp directory, and the file name is a temporary name (so it’s different each time you execute the install).  On a single server installation, VS.Net (and perhaps SQL Server), set the permissions on the WindowsTemp directory so that other apps can write to it…  By not installing VS.Net on this particular machine, that setting was missing.  Once I fixed that, the BizTalk instal finished fine.  This is a simple work around, but one that can kill an evening or two if you don’t know about it.  Enjoy.