Windows 98 and gdiplus.dll
Custom Addressbook needs the standard system file gdiplus.dll. This dll is present on all Windows editions except for some Windows 98 versions and all Windows 95 versions.
Therefore, if you have Windows 95, you will not be able to run Custom Addressbook.
However, if you have Windows 98, just install Custom Addressbook from the zip file or the easy self-installing executable. You can also extract the contents of the zip file to a directory of your choice (no installation needed).
Then start the Custom Addressbook program from its installed location. If the program starts OK you do not need the GDIPLUS.dll file (since it is already on your system). If the program gives a message that it needs GDIPLUS.dll, then the gdiplus.dll file is missing from your computer, you can download the GDIPLUS.dll from one of these links:
Just copy gdiplus.dll into the program directory of Custom Addressbook and then restart it.