.net - new SpeechRecognitionEngine crashes with System.InvalidOperationException: Unsupported format -

.net - new SpeechRecognitionEngine crashes with System.InvalidOperationException: Unsupported format -

i have 2 computers running windows 7 x64 crash on line of code:

var rec = new speechrecognitionengine();

with system.argumentexception: no recognizer of required id found. ---> system.invalidoperationexception: unsupported format.

does have ideas? google hasn't helped. disabled norton didn't help.

the code works on computers, not these 2.

i've tried messing constructor eg thread.currentthread.currentculture , "en-us" , have checked command panel > regional en_us.

many thanks!!

edit: more code @ http://pastebin.com/raw.php?i=1m1wvpfm code pasted above all needed replicate problem on these 2 troublesome pc's.

on problematic computer, built in windows 7 ultimate voice recognition software works perfectly. installed recognizers appear default - 2 installed; en_gb , en_us. en_us 1 getting selected (matches user locale).

.net debugging windows-7 sapi