Delphi program & Windows 64-bit compatibility issue

Question

I have some customers/candidate who complained that my program doesn't work on their Windows 7 64 bit version (confirmed with screenshots). The errors were strange, for example:

in the trial version i am getting a error message whenever i click on \"mark\" \"delete\" \"help\".

error msg is: Access violation at address 0046C978 in module \'ideduper.exe.\' read of address 00000004

windows 7 ultimate 64bit. i7 920 @2.67GHz 9gb or ram

'Mark', 'delete' and 'help' are just standard TToolButton on TToolbar.

The other example is failing to get a thumbnail from IExtractImage.

I have told them to try Compatibility mode but still doesn't work.

The problem is when I tested it on Windows 7 HP 64-bit on my computer (which I've done it before released it actually) it just works fine! So I don't know what causing it

Do you have any advice ?Are different Windows package (home basic,premium,ultimate,etc) treating 32 bit prog differently ?Are the newer version of Delphis (I use 2006) more compatible with 64 bit Windows ? Do I need to wait until 64 bit compiler out?

Thanks in advance

Answer 1

Your best bet in my opinion is to add MadExcept or EurekaLog or something similar to your application and give it to the customer to try again. MadExcept will generate log with stack trace, which will give you a clearer view of what is happening there.

To answer 2nd part of the question, 32bit Delphi programs work fine on 64bit Windows 7. I think it's more likely you have some memory management problems and the customer just happens to stumble upon them while you don't. Use FastMM4 to track those down.

Answer 2

Your applications is trying to access an invalid pointer. Changing environment may surface issues that are hidden in others. Check your application, and use FastMM + JCL+JCVL/MadExcept/EurekaLog to get a detailed trace of the issue. Some Windows APIs may have some stricter call requisites under 7 and/or 64 bit, but we would have to know what your app actually cals.