I'm creating a win32 api program. When i first produced basics class known as WinClass and inherited just like a dozen other classes from this. Now I have to produce a derived class from two classes inherited from base class WinControl and WinHandler.Since I Have desire to make a lot more derived classes from the original dozen, I'm going to use virtual inheritance on like all class inherited from WinClass.Same with there any method of doing this without using virtual inheritance?

Learn to avoid overuse of inheritance whatsoever. For instance, look at this article

http://berniesumption.com/software/inheritance-is-evil-and-must-be-destroyed/

An excellent start to learn to get things done how you need it (using the correct utilization of inheritance) may be the book "Design Designs":

http://c2.com/cgi/wiki?DesignPatternsBook

When i first produced basics class known as WinClass and inherited just like a dozen other classes from this.

And there is the first problem. If WPF has trained us anything, it ought to be that inheritance isn't always the very best model for GUI design.

Same with there any method of doing this Without needing virtual inheritance?

Yes: do not have WinControl and WinHandler be based on WinClass. You have not stated what these do, and so i can't offer any sort of assistance with them. Really, it appears like the thing you need is really a "includes aInch relationship as opposed to the "is really aInch relationship that inheritance brings.

Also, you shouldn't have to make use of boldface for class names. Only use the code tags that StackOverflow provides. Nor it is possible to have to SHOUT in bold-face.