Fix guides for broken files
Real error messages, plain-English causes, and the repair tool embedded right in the guide — usable without leaving the page. Everything runs in your browser.
- Excel File Is Corrupt and Cannot Be Opened — How to Repair .xlsx Without Losing DataExcel says “the file is corrupt and cannot be opened” — why .xlsx files break, the built-in fixes worth trying first, and the browser-side repair tool embedded in this guide.
- How to Fix “File Format or Extension Is Not Valid” — Excel, Word, PDF and MoreThe file format or extension is not valid — what the error actually means, the safe fixes in order, and a browser-side repair tool embedded in this guide for each damaged format.
- There Was an Error Opening This Document — Fix “The File Is Damaged and Could Not Be Repaired”Acrobat refuses your PDF with “there was an error opening this document. the file is damaged and could not be repaired” — what actually broke, the checks worth trying first, and a browser-side repair tool embedded in this guide.
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