How to fix "The installer encountered an error that caused the installation to fail. Contact the software manufacturer for assistance

Hi @Tessa goh,
Thank you very much for posting question to Microsoft Q&A.

According to this issue, may I know if could try these suggestions:

1. Check your Mac's storage: click on Apple at the top left of the screen > System Settings > General > Storage.
2. Try to move the installation file from to another location (for example: you downloaded it and left it "Download" folder, you could try to move it to your desktop and try to run it again.
3. Check permission in Mac: Go to Apple > System Settings > Privacy & Security > Files and Folder > look for Installer and make sure that it is enabled.

For reference, you could check on this article: https://www.macobserver.com/tips/how-to/installer-encountered-error-mac/
Note: Microsoft is providing this information as a convenience to you. The sites are not controlled by Microsoft. Microsoft cannot make any representations regarding the quality, safety, or suitability of any software or information found there. Please make sure that you completely understand the risk before retrieving any suggestions from the above link 
If the methods did not fix the issue, you could try to access to this link: https://learn.microsoft.com/en-us/officeupdates/update-history-office-for-mac#release-history-for-office-for-mac to download older version of Office to see it could help.

Please also let me know which macOS version you are using to have this issue. Did it happen before?
I am looking forward to your reply.

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