"…Another installation is in progress…” error when installing Office
If you see this error message when installing Office, the first thing you should try in restarting your computer. Just bookmark this page in case it doesn't solve the issue.
"We’re sorry, but we could not start your Office installation. Another installation is in progress, please try again later.”
If you get the message again, here's what you need to do:
Press Ctrl + Alt + Delete, and then click Task Manager.
Right-click on OfficeclickTorun.exe and then click End Task. Repeat this step if there is more than one of these.
Click this Fix it.
Then at the bottom of your screen, click Open.
Note If the file doesn’t open, click Save > Open Folder, then double-click the file (it should start with "O15CTRRemove") to run the Fix it tool.
When the Fix it tool finishes, install Office:
If you're a home user, sign in to your account page and click Install.
If you’re a business user, sign in to the Office 365 portal and click Install.
Note There are other ways to uninstall Office you can read about in this article.