[offtopic]
Mystix ... read ... then link ... these are 2 different threads !!!
[ontopic]
just reinstall ESF correctly ... then the "fmod.dll" should be in correct path (ordinary HL-dir)
if you're too lazy look for a fmod.dll which size is 124kB and put it into your HL-dir
then this problem should be fixed
[mod]
this damn thing has often (REALLY OFTEN) reported before !!! use the search function to find the other threads ([off] I need mods here ...)