Simple Excel PlugIn on One Computer will not work on another

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Simple Excel PlugIn on One Computer will not work on another
Simple Excel PlugIn on One Computer will not work on another 
George Spears




Posts: 79
 Joined: 2010-05-06
Hello, I have 2 computers, both running Windows 11. My development computer has Delphi 11.3, Excel 2021, and Add-In Version 10.0 Release (build 1700) (according to the whatsnew.txt file). My laptop had no delphi, and runs Office 365.

I have created the simplest possible Excel add in, which runs fine on my development computer. When I copy the DLL to the laptop and try to install it, I get nothing, but Excel says "Not loaded. A Runtime error occurred in the loading of the COM Add-in". Here are the specifics:

On my development computer:

    Create Directory D:\Projects\ExcelTest
    Use Winzard to create a new project of type ADX Com Add-In
    Project Name: ExcelTest, CoClassName: ExcelTestClass, Register with Admin Priveledges, No InnoSetup, Set project folder to $(BDSPROJECTSDIR)\ExcelTest
    No Office Task Panes
    Click Finish, I see ExcelTest_IMPL
    Build Config is Debug, I set Target Platform to 64 BIT
    I add an adxRibbonTab to the IMPL module, and add 3 RibbonGroups
    Save All, Build ExcelTest

    I open up a CMD window as Administrator. Navigate to D:\Projects\Exceltest\Win64
    I see my ExcelTest.dll, at 7MB
    Run 'regsvr32 Exceltest.dll'. I get a 'succeeded' popup.
    I start excel, and I see my new ribbon. All looks good.

    I copy the DLL to the laptop. (A different directory though, as that directory structure does NOT exist on the laptop).
    On the laptop, I right click on the DLL file, and under properties, I click on 'Unblock', and set security permissions to 'Full Control'
    I open a Administrator level CMD window, and navigate to the proper directory.
    Run 'regsvr32 Exceltest.dll'. I get a 'DllRegisterServer in exceltest.dll succeeded' popup.
    I start excel, but I do not see my new ribbon menu.
    When I go to Excel Options / AddIns / Com AddIns, I see 'Not loaded. A Runtime error occurred in the loading of the COM Add-in'.



I am at a loss as to what else to try. The only thing I can see being different is the versions of Excel. Where do I go from here?
Posted 01 Nov, 2023 11:29:16 Top
Andrei Smolin


Add-in Express team


Posts: 18830
 Joined: 2006-05-11
Hello George,

And Excel on your laptop is 32bit or 64bit?

Regards from Poland (GMT+1),

Andrei Smolin
Add-in Express Team Leader
Posted 01 Nov, 2023 12:19:53 Top
George Spears




Posts: 79
 Joined: 2010-05-06
It is a company supplied laptop, and I never thought about checking the Office/Excel bit level... :(
That was the culprit.

Thank you!
Posted 01 Nov, 2023 12:35:01 Top
Andrei Smolin


Add-in Express team


Posts: 18830
 Joined: 2006-05-11
No problem.

Regards from Poland (GMT+1),

Andrei Smolin
Add-in Express Team Leader
Posted 02 Nov, 2023 09:14:16 Top