Can someone please help me how to correct folloiwig error!!!!!
when run the application not opening DLG3
(code is attached with this as zip file)

1 MB ? lol,

typedef why? what is the wrong.I can't understand

Well, you have:
1. Some problems with not pop pushed registers in the dialog procedures. You end with "ret" while you must "jmp .finish".
2. Your IDs for the buttons are the same - I mean IDB_BITMAPBTN*
3. Also, why you use "CS" in CreateWindowEx as a lpParam argument ??? "0" is enough and safe.
4. Using 1meg of bitmaps as a button pictures, IMHO is not good for assembly application. (It is not good for HLL app as well).

Thanx JohnFound, I don't have much knowladge in programming.(may be because I am learning it by my self)but can understand 1-3.
But why in assembly language we cannot use lot of bitmaps? and if we want to develop a application which need lot of resources(may be bitmaps) what will we do?
(i'v attached the corrected code with this)

mns, of course you can use bitmaps of whatever size you want.
It is, how to say it - "matter of style".
The assembly applications are known as optimal, small and fast.
As an illustration your image pp1.bmp is 24bit bitmap. The size of this image is 220kbytes. There are only 2 colors in the image - if you save it in 2 color bitmap - the file will be only 10kbytes in size.
If you use some compressed format, the size becomes even smaller:
In PNG - 472bytes!
Another level of approach is to draw the buttons on the fly - your buttons are very simple and you simply don't need bitmaps for such simple images.

Hey now I understand what you have said.
Thank you very much JohnFound.I really appriciate your thought.
Thanx again Bro!

Images, like ICO and BMP can be loaded from files by LoadImage API.
This way they do not take room in EXE file and they can be loaded when needed minimizing the application startup time.

Thanx! AsmGuru62