Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
I've had this problem for a few months already on my new laptop. I was able to open some EXCEL files, but not others and couldn't open new files. I had office 2016 trial first, then 360 trial, before finally purchasing office 2016 home. I suspected the issue was because of my trial programs. But it seems my problem has been cleared by chance today. I was trying to clear a WORD issue, and I found that my Temporary Internet Files folder was missing and the registry pointing to a different folder. After following the instructions, my excel is now opening without any issues. I hope this helps to resolve your issue.
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