Thanks both for your replies - I think I may well try to change the way it writes, as Jon Hulatt suggests. This will obviously mean writing my own packer utility too (I was using WinZip to pack and then my own program only needed to unpack), but that shouldn't be too bad. Thanks again, KB

Hi, I have written a file packer for a game engine. The packer uses Zip compression (based on the zlib library), and so any packed files can easily be opened with WinZip, EnZip etc. However, I would like to give them better protection. Currently they can be password protected (and the password is encrypted), so people can open the zip file but not extract any of the contents. However, I was wondering if there was any way to make the Zip file unreadable to WinZip etc and only readable to my program. Any suggestions would be much appreciated. Many thanks, KB

Hi, many thanks for your reply. I tried the rgn method, and finally got this code working: hOrgRgn=CreateRectRgn(0,0,0,0); GetWindowRgn(hWnd, hOrgRgn); hRectRgn = CreateRectRgn(50, 10, 200, 200); hResultRgn=CreateRectRgn(0,0,0,0); CombineRgn(hResultRgn, hOrgRgn, hRectRgn, RGN_XOR);//RGN_DIFF); //rgn_diff makes no difference SetWindowRgn(hWnd, hResultRgn,TRUE); But unfortunately, this does exactly the *opposite* of what I want. This cuts out a square from the middle of the window, but it only shows the cut out square and not the rest of the window; I want to show the window with a square hole in the middle. I've tried swapping around "hOrgRgn" and "hRectRgn" in CombineRgn(), but it makes no difference. Does anybody have any suggestions? Again, many thanks, Keith

Hi, I want to create a dialogue box that has a hole in it... Essentially, it is a window that covers another window created by another application. But I want a square hole in my dialogue that shows part of the window beneath it (kind of like those envelopes that you get with a square cutout in the front showing your address that is printed on the letter it contains). Does anybody know how I can do this? I am using the Windows API. Many thanks for any suggestions, Keith

Hi, I am trying to write a small utility that allows users to customise the icon of my program, which is a precompiled EXE (similar in function to MicroAngelo etc, but much simpler, with only the option of choosing the new icon, which will then be applied to the EXE). I believe UpdateResource() can do this for NT (and the _UpdateResource class over at http://www.codeguru.com/misc/resources.html does pretty much the same for Win 9x). However, I can't figure out how to use UpdateResource correctly. I can't even get the sample code from MSDN to compile correctly. Could anybody tell me how I can use BeginUpdateResource(), UpdateResource() and EndUpdateResource() to swap the icon in an EXE file for another .ico file (ie the end user will just have to select an .ico file)? Many, many thanks to anybody who can help or give me any pointers. All the best, KB