There is somrthing wrong with QV 10 SR 4 and also with QV 11, and this error appears quite often.
What you can do is that just try to reload it 2-3 times, if the error appears all times then contact Qliktech, because What I see is that sometimes same action will trigger this error and sometimes it will not.
You are right. Sometime it will trigger this error and sometimes it will not. So I have send email to Qliktech support. (email@example.com). For your information, this error happen on 32-bit version only. I tried in 64-bit version, it run successful without error message.