Prevent New Instances of Excel 365

pliskers

Active Member
Joined
Sep 26, 2002
Messages
441
Office Version
  1. 2016
Platform
  1. Windows
I am trying to prevent Excel 365 from opening a new instance of the application when I double click on a file name in Windows Explorer. I've seen various solutions posted for earlier versions, related to the Option to "Show all windows in the taskbar", but that option does not appear to be available in Excel 365.

I get error messages from the opening of the second instance due to the presence of a Personal.xlsb file that holds my frequently used macros. I'd like all newly opened files to appear in the same instance unless I choose to open a second one.

Is there a way to prevent this from happening?

EDIT:
Just a follow up to be clear: If I use the File-Open method in Excel, the second file will open in the same instance. What I'm looking for is a way to prevent a second instance from opening when I have one file already open and double-click a second file in Windows Explorer. That's what I'm inquiring about.
 
Last edited by a moderator:

Excel Facts

Format cells as time
Select range and press Ctrl+Shift+2 to format cells as time. (Shift 2 is the @ sign).

ranman256

Well-known Member
Joined
Jun 17, 2014
Messages
2,173
dbl-clicking the file outside of Excel will begin a new instance. Win-OS is doing it, not excel.
 

Strithken

New Member
Joined
Jan 5, 2022
Messages
18
Office Version
  1. 365
  2. 2016
Platform
  1. Windows
This sounds like the "Ignore other applications that use Dynamic Data Exchange (DDE)" option is checked.

To uncheck this, use Application.IgnoreRemoteRequests = False or navigate to the option: File -> Options -> Advanced -> Scroll down to General Section -> Ignore other applications...

When you are double-clicking on the file in the File Explorer, Windows is using DDE to send data to the instance of Excel. If that value is set to True, the existing instance of Excel ignores the data and a new instance of Excel is opened (that's what's supposed to happen anyway... doesn't work for me). Any change in this setting is persistent (written to the registry when the application closes; I've observed it is not persistent when changed in Safe Mode).
 

pliskers

Active Member
Joined
Sep 26, 2002
Messages
441
Office Version
  1. 2016
Platform
  1. Windows
This sounds like the "Ignore other applications that use Dynamic Data Exchange (DDE)" option is checked.

To uncheck this, use Application.IgnoreRemoteRequests = False or navigate to the option: File -> Options -> Advanced -> Scroll down to General Section -> Ignore other applications...

When you are double-clicking on the file in the File Explorer, Windows is using DDE to send data to the instance of Excel. If that value is set to True, the existing instance of Excel ignores the data and a new instance of Excel is opened (that's what's supposed to happen anyway... doesn't work for me). Any change in this setting is persistent (written to the registry when the application closes; I've observed it is not persistent when changed in Safe Mode).
Exactly what I needed - thank you!
 
Master Excel Bundle

Excel contains over 450 functions, with more added every year. That’s a huge number, so where should you start? Right here with this bundle.

Forum statistics

Threads
1,164,282
Messages
5,836,396
Members
430,425
Latest member
xlsee

We've detected that you are using an adblocker.

We have a great community of people providing Excel help here, but the hosting costs are enormous. You can help keep this site running by allowing ads on MrExcel.com.
Allow Ads at MrExcel

Which adblocker are you using?

Disable AdBlock

Follow these easy steps to disable AdBlock

1)Click on the icon in the browser’s toolbar.
2)Click on the icon in the browser’s toolbar.
2)Click on the "Pause on this site" option.
Go back

Disable AdBlock Plus

Follow these easy steps to disable AdBlock Plus

1)Click on the icon in the browser’s toolbar.
2)Click on the toggle to disable it for "mrexcel.com".
Go back

Disable uBlock Origin

Follow these easy steps to disable uBlock Origin

1)Click on the icon in the browser’s toolbar.
2)Click on the "Power" button.
3)Click on the "Refresh" button.
Go back

Disable uBlock

Follow these easy steps to disable uBlock

1)Click on the icon in the browser’s toolbar.
2)Click on the "Power" button.
3)Click on the "Refresh" button.
Go back
Top