AcceptButton doesn't work in case there are TabControl on the form

In the following fo开发者_Go百科rm, I want the AcceptButton to be OK button, but although I set the property to the Form that OK button is the accept button, the actual result is Test button.

How to fix it?

Earlier i got this kind of problem, but got solved easily. It is very much possible that Test button TabIndex is less than that of OK button. Just make it reverse. It should work. At least it worked for me. If not, just check the TabControl TabIndex, it should also be greate than your OK button. Hope it helps.