Need help to develop old FoxPro App made by non existing developer

[Sadlr]

Hi Everyone,
22 years ago I bought an old foxpro (P.O.S application) I still use it till now,
but I need to develop and modify most of it. So far the person I bought from is not existing anymore.

Otherwise I hardly can find developers for foxpro in my town in Egypt to make good use of this great app.
I am looking here for help, I am not professional but i can learn and I have some work experience.

My first question:
The app were coded with version 6, and the machine run Windows 10 32Bit.

How to fix These error messages which appear when I do any action :

RTOL run-time error’453’:
Specified DLL function not found

 

[Mike Lewis]

Hello Sadlr and welcome to the forum.

I'm afraid these errors are going to be very difficult for us to debug without knowing a lot more about the code that is causing them. They are not standard Foxpro error messages, but are presumably generated by the application itself.

In general, "Specified DLL function not found" could mean that a DLL file is missing from the run-time environment. It might be present on the developer's machine but not on the end-users. This is something you should be able to easily check.

Or it could mean that the DLL is present, but it is not the same DLL that the program is expecting (perhaps a different version, or a completely different file which happens to have the same name).

Or it could mean that there is an error in the code: using the wrong name when declaring the function (with a misspelling or perhaps an issue with case sensitivity). It's impossible to check that without seeing the code. But if this is the case, the chances are the error would have occurred long before now.

You say you purchased the application 22 years ago. Has it been in use all the time since then? If so, have these errors only just stated to occur? If so, then you must try to work out what has changed in the environment. What is different now compared to the last time the application ran without the errors? You mentioned, for example, Windows 10. Have the errors only started after you moved the app to a Windows 10 system? Or has there been some other change recently?

Mike


__________________________________
Mike Lewis (Edinburgh, Scotland)

Visual FoxPro articles, tips and downloads

 

[Koen Piller]

Sadir,

There are a lot of programmers from India on the Foxite Forum.
My best bet is to ask them to rewrite your POS application into VFP9SP2 with that conversion you are ready for the next 22 years.Should not be to expensive.

Stay healty,
Koen

 

[GriffMG]

Hmmm

It wouldn't be this product would it?

http://www.shinetechlab.com/vision-2000-ERP.html

Regards

Griff
Keep [Smile]ing

There are 10 kinds of people in the world, those who understand binary and those who don't.

I'm trying to cut down on the use of shrieks (exclamation marks), I'm told they are !good for you. ​

 

[Sadlr]

Have the errors only started after you moved the app to a Windows 10 system?

Mike, thank you, the only change is the windows platform, its still work great under 95/98 windows without any errors,

 

[Sadlr]

My best bet is to ask them to rewrite your POS application into VFP9SP2

Thanks Koen, any recommendations would be appreciated.

 

[Sadlr]

It wouldn't be this product would it?

Griff,
I will try to connect them, maybe !!!

 

[Mike Lewis]

the only change is the windows platform, its still work great under 95/98 windows without any errors,

In that case, it's likely that a DLL file is missing from the Windows 10 system.

Start by checking the names of all the DLL files in the application's folder on your old system. The application folder is the one in which the EXE file is stored. Look also in folders below the application folder. Then compare that list to the DLLs in the corresponding folders in the Windows 10 machine. If any are present in the old machine but not the new one, then copy them across (to the equivalent folder on the new machine).

If that doesn't help: Do you have the source code for the application? If so, can you work out which line of code is causing the error? If so, let us know; that might help us figure out what is wrong.

Also, if you have the source code, can your search if for any commands beginning with the word DECLARE and containing the word IN (for example, DECLARE Sleep IN Win32API)? Make a list of all the file names immediately after the word IN. Those will include the DLLs the should be present on the new machine. Let us know what those files are, and we might be able to take it from there.

Mike

__________________________________
Mike Lewis (Edinburgh, Scotland)

Visual FoxPro articles, tips and downloads

 

[tomk3]

Hello,

you may try process monitor (procmon) from sysinternals / microsoft
It shows in realtime which registry, files a process trys to access, so you may find out the missing dll.

Hint : Have a look on filter when using it.

https://docs.microsoft.com/en-us/sysinternals/downloads/procmon

Regards
tom

 

[Sadlr]

Start by checking the names of all the DLL files in the application's folder on your old system

This option is really hard to me to proceed.

Also, if you have the source code,

I think this option is good for me if we can search for any commands in the below source code.

 

[Sadlr]

It might help; this error occured under win10 64Bit

 

[herbstgy]

an easier approach without knowing the source code:
check what dll's are on the old machine in the program's directory, and copy those dll's to the new machine

 

[Mike Lewis]

Sadlr, you say that it is hard for you to check the DLLs in the application's folder. Why is that hard?

Just navigate to the application's folder in Windows Explorer. Set the view to "Details". Then click on the header of the Type column. You will see all the DLLs grouped together, with the Type column showing "DLL File". Those are the ones you are concerned with.

If you don't know which is the application's folder, look for the shortcut from which you launch the application. Right-click on the shortcut and choose Properties. Look in the Target field to see the directory in question.

Now do the same on the new machine. If there are any DLLs that are present in the old system but not the new ones, those are the ones you need to copy across.

Mike

__________________________________
Mike Lewis (Edinburgh, Scotland)

Visual FoxPro articles, tips and downloads

 

[Sadlr]

That was easy, I checked the 3 DLL files in the old directory which are the same in the new one, I tried to overwrite or remove them all but did not fix the errors.

 

[herbstgy]

possibly you need to register the dll's.
try "regsvr32 <dllname>" in command line in the program's directory, with admin rights.

 

[Mike Lewis]

If the DLLs were the same, then there is no point in copying them across. And no need to register them.

Mike

__________________________________
Mike Lewis (Edinburgh, Scotland)

Visual FoxPro articles, tips and downloads

 

[Sadlr]

possibly you need to register the dll's

I did that option

 

[Koen Piller]

HI,

You can download a new version at :

https://www.google.nl/search?sxsrf=...aoEkgEBOJgBAKABAaoBB2d3cy13aXo&sclient=psy-ab

or google for OC25.dll

Stay healthy,
Koen

 

[Sadlr]

You can download a new version

Thank you, this is work for the 32Bit machines, but still occurs on 64Bit.

the first above pic for the Win10/32Bit, when I replace the dll files the two errors stop appearing.
the second pic is the appearing error under win10/64Bit, updating dlls did not fix it yet.

Thank you for helping, it was an annoying bugs.
Sadlr