How to change default app to choose a Batch file instead of a Microsoft Store App?
If Outlook Attachment (heavy Excel file in my situation) can open with command line switches, it will be separate instance from existing Documents. This improve freezing of existing Documents as per my understanding.

1. Typical day for me is I work on Office apps (mainly Excel) with several workbooks open. They :
1. use Indirect functions which are volatile
2. named formulas which are typically in development phase and therefore tend to violate recommendations listed in Excel
2010 Performance: Tips for Optimizing Performance Obstructions | Microsoft Docs until I finished finalizing them.
3. occasionally, there's urgent need to print Outlook Excel attachment which is typically heavy and likely causing my
currently opened documents to freeze (same Excel instance as attachment).
4. To prevent my currently opened Excel documents to freeze, I have to close all open Excel and re-open them after printing
the Excel attachment.


My question:
1. In my computer
1. Excel property in Windows 10 toolbar is ""C:\Program Files (x86)\Microsoft Office\root\Office16\EXCEL.EXE" /x"
2. opening Outlook attachment results in same Excel instance as currently opened documents.
2. If Your computer opens attachment in new instance.
1. How did you setup your computer to open attachment in new instance?



https://answers.microsoft.com/en-us/...7-68404d1f6ec8