Hi Wim, That message is printed when muscle's GetRunTime64() function detects a bug in the behaviour of Windows' QueryPerformanceCounter() function and tries to work around it by falling back to the lower-resolution (but more reliable) timeGetTime() function instead. Details about the bug (which only occurs on certain motherboards) can be found here: http://support.microsoft.com/default.aspx?scid=kb;en-us;274323 AFAIK the work-around works pretty well, so there shouldn't be any real problem -- well, okay, there is one, and that is that timeGetTime()'s value resets back to zero after about 49 days, which means that if your program is relying on GetRunTime64() for anything, it will probably break after 49.7 days of uptime. :^( -Jeremy > Hallo, > > I get the message on muscled : Queryperformancecounter() is buggy, > reverting to timeGetTime() methode instead . > > > What does this mean ? Is there a problem ?