Hitting the BREAK on an Excel runaway, causes ALL eXcel workbooks to close

Question

Hitting the BREAK on an Excel runaway, causes ALL eXcel workbooks to close

Art L 40

Using Office 2019 on Windows 11, recently converted from Windows 10.

When I have a single Excel macro-enabled workbook open, and it is in some runaway endless-loop state, hitting "BREAK" will end execution as expected ... and bring up the dialog to "debug" or "end", allowing for inspection of the vba code.

When I have MULTIPLE workbooks open, and I hit BREAK on the during the execution on ONE of them, ALL Excel workbooks close WITHOUT WARNING leaving all pending changes unsaved, and leaving nothing for inspection.

Not sure whether this operated the same way under Windows 10.

4 answers

Your answer

Answer 1

Kimberly Olaño 19,855 Independent Advisor

Hello! Art. Thanks for the details.

What you’re seeing is not normal Excel behavior, hitting Ctrl+Break (or using the Break button on a full keyboard) should only interrupt the currently executing VBA project, not crash the entire Excel instance and close all open workbooks unsaved.

Try to run Excel in separate processes:

Instead of all workbooks sharing one process, launch each in its own instance:

Open Excel, then use File → Options → Advanced → General → "Ignore other applications that use Dynamic Data Exchange (DDE)" → check it.

Then start Excel from the Start menu again for each workbook. Each instance will be isolated — if one crashes, the others remain open.

See if this helps. If you need further assistance, just let me know.

Best regards,

Kimberly

Art L 40 Reputation points

2025-09-23T16:05:15.4266667+00:00
That does not work.

It will not create a separate instance of Excel each time you run it... or each time you right-click on the excel icon on the task-bar and select "excel".

But I did find out what DOES!

You have to install the following key in the registry with a value of 1.

Windows Registry Editor Version 5.00 [HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Excel\Options] DisableMergeInstance"=dword:00000001

Only THEN will Excel create separate instances. And YES... that WILL solve my problem.

HOWEVER, even with a single instance having multiple open workbooks... in it NOT ACCEPTABLE for excel to close other workbooks when I do a break on just ONE of them.

Answer 2

Kimberly Olaño 19,855 Independent Advisor

Have you tried testing without add-ins?

Go to File → Options → Add-ins.
At the bottom, change Manage: COM Add-ins → Go... and disable them.
Restart Excel and see if the crash still occurs when hitting Break.

Art L 40 Reputation points

2025-09-23T20:14:53.3566667+00:00

That made no change, if the Registry key was set to zero.

Separate instances occur only if the registry key is set to 1.

And multiple open workbooks under a single instance still all close if ONE of them is interrupted with BREAK.

Answer 3

Kimberly Olaño 19,855 Independent Advisor

Got that. File → Account → About Excel → check if you’re on Excel 2019 build 103xx or newer. Some interim builds have regressions that later patches resolve.

Art L 40 Reputation points

2025-09-24T02:19:06.38+00:00

Version 2508 Build 16.0.19127.20192) 32-bit

Which brings up another question:

When I bought 2019 Office, I downloaded the 32 bit version because I still run an old 32bit version of VISIO, and was afraid that it may not run together with 64bit Office.

Do you think that i can switch to 64 bit office without losing my Visio (2003) capability.

Answer 4

Kimberly Olaño 19,855 Independent Advisor

Microsoft officially does not support mixing 32-bit and 64-bit Office components on the same Windows machine. That means if you install Office 2019 x64, you can’t keep Visio 2003 x86 running alongside it in the same “Office family” space.

The Office installer will either refuse the install or force you to uninstall the 32-bit component first.

Share via

Hitting the BREAK on an Excel runaway, causes ALL eXcel workbooks to close

4 answers

Your answer