What is a good replacement for "ununderstandable"?

I want to tell a colleague of mine I'm doing something that will prevent her from getting "ununderstandable" errors. I have:

...so that you will not get unnecessary, [ununderstandable] errors.

After googling "ununderstandable", I see that there is no such word, but I'm still looking for something that sounds better.


Solution 1:

How about incomprehensible or unfathomable?

Solution 2:

I prefer unintelligible.

Solution 3:

Enigmatic, abstruse, obscure or cabalistic sound good to me.

Solution 4:

...so that you will not get unnecessary cryptic error messages.