Word or Excel file corrupt and won’t open? What to do

You double-click a Word document or Excel spreadsheet you have used for months and, instead of your work, you get an error. The laptop crashed while it was open, the power went off, or a USB stick was pulled out before it had finished saving. Now the file refuses to open. Sometimes Office can repair it in seconds; sometimes the file is empty and the real job is finding another copy; and sometimes the file is fine and the drive underneath it is failing. This guide walks through the safe order of things to try.

The error messages you might see

• Excel: “Excel cannot open the file because the file format or file extension is not valid. Verify that the file has not been corrupted and that the file extension matches the format of the file.”
• Word: “Word found unreadable content in [file]. Do you want to recover the contents of this document?”
• Word or Excel: “The file is corrupt and cannot be opened.”
• The file opens but shows nothing, random symbols or only part of the content.

These messages mean Office could not make sense of what it read. They do not tell you why. The cause could be a save that was cut off, a sync conflict, or a storage device that is returning bad data.

Step 1: make a copy before trying anything

Before you repair anything, copy the damaged file to another location, such as your desktop or a different drive, and work only on the copy. Repair tools can save over the original, and if a repair makes things worse you want the untouched file to go back to.

If the copy itself fails with an error, or takes far longer than it should for one small file, stop there and skip to the section on storage problems below.

Step 2: check the file size

Right-click the file and choose Properties (or Get Info on a Mac) and look at the size.

• 0 bytes or a few KB for a document that used to be large means the content was never written. No repair tool can rebuild what is not there. Go straight to Step 4 and look for earlier versions.
• A normal size means the data may still be inside the file and a repair is worth trying.

Step 3: use Office’s own repair

Do not just double-click the file again. Open Word or Excel first, then:

1. Go to File > Open > Browse and find the copy you made.
2. Select the file, click the small arrow next to the Open button and choose Open and Repair.
3. In Excel, choose Repair first. If that fails, try again and choose Extract Data, which recovers values and, if you choose, formulas, without formatting.
4. In Word, if Open and Repair fails, try the file type list in the Open box and choose Recover Text from Any File. You lose formatting but often get the words back.

If the file opens after repair, save it straight away under a new name and check it carefully, especially formulas, totals and tables.

Step 4: look for another version

Very often the quickest fix is an earlier copy of the same file:

• OneDrive or SharePoint: right-click the file online and use Version history to restore an earlier save.
• Windows Previous Versions: right-click the file or its folder, choose Properties and open the Previous Versions tab. This only shows entries if File History or restore points were set up.
• Email: search your sent items for the file name. A copy you emailed last week may be all you need.
• Office AutoRecover files in Word and Excel (File > Info > Manage Document), which sometimes hold a more recent version than the saved file.
• Your backup drive or company server, if you have one.

When the real problem is the storage

A corrupt Office file is sometimes the first symptom of a failing hard drive, SSD, USB stick or memory card. Suspect the storage if:

• several files have gone corrupt at once, not just the one that was open during the crash;
• photos open half grey, or other file types also refuse to open;
• copying files is very slow, freezes or ends with errors such as “Cannot read from the source file or disk”;
• the computer has become slow, keeps freezing, or the drive is making clicking or ticking noises;
• Windows asks you to scan and fix the drive, or to format it.

In that situation, stop opening and repairing files. Every attempt reads the damaged areas again, and a weak drive can get worse with use. Do not run CHKDSK or format the drive. Shut the device down and keep it as it is. If the files were on a USB stick or memory card, do not keep saving new work to it.

A recovery lab can make a sector-by-sector copy of the device and recover files from that copy, so the original is not stressed further. We cover laptops on our laptop data recovery page and external drives, USB sticks and memory cards on our external drive and flash media recovery page.

Avoiding it next time

• Always use Eject or Safely Remove before unplugging a USB stick or external drive.
• Keep important documents in a folder that is backed up or has version history, such as OneDrive or a regularly backed-up server.
• Keep AutoSave or AutoRecover switched on in Word and Excel.
• Have at least one backup that is not plugged in all the time.

Still can’t open it?

If repair has failed, there is no other version, or you think the drive itself is failing, call Data Retrieval on 020 7064 4996. We offer a free assessment with no obligation, or you can request a quote online.