If, after installing updates or upgrading to Windows 11/10, you find that some of your Microsoft Word, Excel, or PowerPoint documents do not open, then this post may be able to help you.
Office documents do not open
You may receive one of the following errors:
Word experienced an error trying to open the file
This Excel file is corrupt and cannot be opened
The application was unable to start correctly, PowerPoint found a problem with the file or PowerPoint can’t this read.
This is happening because Microsoft Office is trying to open an Outlook attachment from untrusted locations in Protected Mode, and failing. In such cases, it is not recommended to disable Protected View. Protected View helps keep your computer secure & safe. Files from the Internet and from other potentially unsafe locations can contain viruses, worms, or other kinds of malware, which can harm your computer. To help protect your computer, files from these potentially unsafe locations are opened in Protected View.
If you receive such errors, Microsoft suggests that you first ensure that your Microsoft Office is updated to the latest version. If you use Avast antivirus, make sure that it too is updated to its latest version.
If updating fixed the problem, great; else do the following:
Open an elevated command prompt, type the following and hit Enter. Remember to use YOUR Office version number. I have used Office 15 here,
icacls "%programfiles%\Microsoft Office 15" /grant *S-1-15-2-1:(OI)(CI)RX
You will see a Successfully processed message.
See if you are now able to open Office documents. You should be able to.
If not, then you may want to Repair Office.
Let us know if anything helps you.
This post will help you if you receive Office is busy error message.