Multiecuscan

hi all,
come to use fecuscan for first time in ages and it just crashes. if tried reinstalling latest version but still the same problem in fact the software wont unistall from its own uninstall option just crashes again. this is what it says

Error signatute
eventtype :clr20r3 P1:multiecuscan2.exe P2:3.2.0.0 P3:4e3ee5b8 P4:mscorlib P5:2.0.0.0 P6:4a7ce2b8 P7:196 P8:e4 P9:system.io.filenotfoundexception

any ideas please? as it used to work just fine

Phil

ok updated to netframework3.5 and bingo back working. but i dont understand why it stopped