No Longer Record .WAVs


Extraordinary Member
Hello again,

Suddenly I can no longer record .WAVs on all but one programme.

I get two errors:
Audacity - 'Error opening recording device, Code 9999. Unanticipated host error'
RecAllPro - Can't open wave device for input. Close other programmes using wave.

Windows 10 Pro v1909.

Could this be the problem: KB4551763 Cumulative Update, installed just before all this started, or possibly the one before 4551762 which apparently had issues ?

How to fix it?


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Are you recording using an external mic or something that was built-in? You mentioned you can no longer record "on all but one programme."
Which one works? Is it possible that your mic properties were somehow screwed up? This would explain why only one program works since the mic may no longer be recognized by others.


Extraordinary Member

I can't record anything external to the computer from LineIn or StereoMix despite these being set up correctly in Control Panel. It cannot see any audio I put on LineIn.. It will not even record from Net radio and videos etc either. Net radios which have their own recording systems built-in do work. The Mic doesn't come in to it!

Actually I can't record anything at all, despite my saying 'but one'.

Incidentally there are two sound systems showing in Device Manager, Realtek and AMD. Disabling AMD makes no difference. It isn't a driver problem as it insists drivers are up-to-date.

I'll take it to a computer shop on Monday in the hope they can fix it, as I had the same problem on this other Win-10 machine earlier. Hoping it's not a hardware problem.

Thank you for your time.