All of a sudden my Arturia The Laboratory controller is no longer working in X3 Pro. However, if I check only the input, then click apply, and then check the output, and then click apply, the Laboratory will work again.
 
There is a box when the error message comes up that says, Midi Device Failure, and then Reason as reported by Windows: Not enough memory.
 
Any ideas?

I'm having the same issue. Did you ever get this resolved?
 

You don't mention the operating system, but is there any chance you've hit the Windows MIDI Port Limit?

Operating system is Windows 7 Ultimate. I don't think I've hit the Windows Midi Port Limit.
Thanks for your response.

osgoodeian
Operating system is Windows 7 Ultimate. I don't think I've hit the Windows Midi Port Limit.

You won't know unless you follow the directions in the article to check out the status of hidden ports. The problem is that Windows creates duplicate ports if you plug a USB device into two different USB ports. And it remembers them, so if you tested out an interface in two different ports, that's two more ports that go against the limit even if you never use that device again. I'm not saying that's the problem; it probably isn't. However if you exceed that limit, unpredictable things can happen.
 

I've checked - using the system above - my midi ports, I'm nowhere close to 10.
Ian

Have you tried Arturia support? They might have encountered this before and have a solution. 

I'm not sure how but the situation has resolved itself!
Thanks for your help!