ok... thats it... Didn`t firgure it out yet... As I said: it does only happen if I use a different directory (or assembly) than the default ones provided by upp like 'examples', 'uppsrc' etcetc...).
One mor ething to note is:
if I install the mingw-compiler version of upp including the mingw libraries I can use the msvc compiler from anywhere. The error From above does only occur, if I only use msdev 8.0 compiler...