Unalterable Excel 2016 spreadsheet always crashes

An spreadsheet I've worked with for over 10 years is now oddly unusable.

I can load it. Everything is there. But if I try to do anything with it - even copying a single cell, delete a cell or row, or checking for errors - it crashes.

I've disabled KuTools, but that made no difference.

I've 'repaired' MS Office, but this made no difference.

I've run a maintenance program (System Mechanic); no difference.

I would appreciate any tips as to how I can do any repair or fix.

Are you able to edit it on another computer?

Excellent suggestion.

Alas, I'm travelling just now so cannot easily do so. The only other person I know with a computer doesn't use Excel 2016.

But when I get home in 10 days, I'll try that if I've not found a way before then. However, it may not work, so I'd still appreciate any other suggestion.

Going back to a last known working version (if you have one).

Thanks. I do have one, going back three days; so not a total disaster. But, as I usually do, I made that before I did a set of major changes to the spreadsheet - took hours.

So altho' I'll survive, I had hoped - perhaps unrealistically - that there may be something I could try that could get me able to use the now compromised version.

Thanks you. Your ideas have led me to get at least part of the way.

My file is xlsm.

I did copy the file. It did open, with macros disabled (I don't think this had happened before); I made changes and saved them. They have stuck. So perhaps this is going to work.

Great relief. Much appreciated.

You are welcome.

If that takes care of your original question, & to say Thanks, please click on Add Reputtion (bottom left corner of the post of the person(s) who helped you)
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Thank you.