Fix guides
Find the error message you are looking at. Each guide explains what it means, what to try first without any tool, and which repair tool can help. The tools run in your browser, so your files are never uploaded.
Word, Excel and PowerPoint
Documents that Office says are corrupt or unreadable.
- Word says it "found unreadable content" or the .docx is corrupt
What Word's "found unreadable content" and "we can't open this file" errors mean, what to try first, and how to repair a damaged .docx in your browser.
- Excel says the file format or extension is not valid, or it found unreadable content
Why Excel refuses an .xlsx ("file format or file extension is not valid", "found unreadable content"), what to try first, and how to rebuild or extract the data.
- PowerPoint found a problem with content, or the .pptx needs repair
What PowerPoint's "found a problem with content" and repair prompts mean, how to pull the slides out for free, and how to repair a damaged .pptx in your browser.
PDF and e-books
PDFs that won't open, unsafe redactions and broken e-books.
- "There was an error opening this document. The file is damaged and could not be repaired" (PDF)
Why a PDF says it is damaged or can't be repaired, what to try first, and how to rebuild the file's structure in your browser.
- Is my redacted PDF safe? Black boxes drawn over text can still be copied
Why black boxes on a PDF often don't remove the text underneath, how to test your file for free, and how to check it in your browser without uploading it.
- EPUB won't open, is "invalid", or has an empty or broken table of contents
Fix an EPUB that a reader refuses to open or that shows a blank or broken table of contents, with free checks first and repair tools that run in your browser.
- PDF won't let me copy, print or edit: "security settings prevent" (owner restrictions)
What a PDF's permissions restrictions are, the difference between an open password and an owner password, and how to remove restrictions from a PDF you're entitled to change.
- Print shop rejected my PDF: "fonts not embedded" (PDF/X, preflight)
What "font not embedded" means in a PDF preflight, how to re-export with fonts embedded, and how to list the fonts a PDF uses and which are missing.
- PDF signature invalid: "document has been altered or corrupted since it was signed"
What a PDF's "altered since it was signed" warning means, common reasons a valid signature breaks, and how to check in your browser whether the signed content changed.
Archives, backups and databases
ZIPs, phone backups and databases that fail to open.
- ZIP file is corrupt: "unexpected end of archive", "invalid or corrupt zip", "headers error"
How to recover files from a damaged ZIP that shows "unexpected end of archive", "the compressed folder is invalid" or "headers error", with free options and a browser tool.
- Android .ab backup won't restore: extract the files without a phone
How to get the files out of an Android .ab backup that adb restore rejects or that you can't restore to a phone, including cut-off and damaged backups.
- SQLite: "database disk image is malformed"
What SQLite's "database disk image is malformed" means, the built-in .recover command, and how to export tables from a damaged database in your browser.
- .eml email file won't open or shows garbled attachments
Why a saved .eml message won't open or its attachments are missing (broken headers, mismatched MIME boundary) and a browser tool that repairs the structure.
Photos, video and audio
Cut-off pictures and clips, memory cards and RAW files.
- "moov atom not found": a video file that won't play or was cut off
What "moov atom not found" means, when a cut-off MP4 or MOV can and cannot be repaired, and a browser tool for the cases that can.
- JPEG or PNG cut off, grey at the bottom, or "premature end of JPEG file"
Why a photo shows only the top half, has a grey bottom or won't open, what to try first, and how to repair a truncated JPEG or PNG in your browser.
- WAV file shows 0 seconds, won't play or is silent after an interrupted recording
Why a recorded WAV file has zero length or won't play, how to open it as raw audio for free, and how to repair the header in your browser.
- SD card not recognised, "You need to format the disk": recover photos and files
What to do when a memory card says it must be formatted: what not to do, how to image it, and how to carve photos and documents out of the image in your browser.
- RAW photo (CR2, CR3, NEF, ARW, DNG) won't open or is corrupt
What to do when a camera RAW file is corrupt or unsupported, and how to rescue the JPEG preview stored inside it in your browser.
- Subtitles out of sync, overlapping or broken in an .srt or .vtt file
How to fix subtitles that are late or early, overlap, or fail to load: free player shortcuts, and a browser tool that shifts timestamps and repairs SRT and WebVTT files.
- M3U / M3U8 playlist won't load or plays the wrong files
Why a media or IPTV playlist won't load (missing #EXTM3U, bad #EXTINF lines, backslashes in paths) and a browser tool that repairs it while keeping IPTV attributes.
- GPX file won't import into Strava, Garmin or a map app
Why a GPX track fails to import (invalid XML, bad coordinates, points out of order) and a browser tool that cleans the track.
Fonts, design files and games
Fonts, Photoshop files, torrents and Minecraft worlds.
- Font can't be installed: "the font file is corrupt" or "not a valid font file"
Why Windows or macOS refuses a .ttf or .otf font, what to check first, and how to repair a font's table checksums and structure in your browser.
- Photoshop file is damaged: "the file-format module cannot parse the file"
What Photoshop's "file-format module cannot parse the file" means, which free apps may still open the PSD, and how to rescue the flattened picture in your browser.
- "Invalid torrent file": a .torrent that your client rejects
Why a torrent client says the .torrent file is invalid or can't be parsed, and how to repair a damaged .torrent and get its magnet link in your browser.
- Minecraft world won't load: corrupted level.dat or region file
How to recover a Java Edition Minecraft world with a corrupted or missing level.dat or a bad region file, including the free level.dat_old trick and a browser repair tool.
- DXF file won't open in AutoCAD or a CAD viewer (invalid or damaged)
Why a DXF drawing fails to open or reports errors, what to try first, and a browser tool that repairs damaged text DXF files.
- InDesign IDML file won't open or is reported damaged
Why an InDesign .idml file won't open, what to try first, and a browser tool that repairs the package without editing your text or page geometry.
- Illustrator .ai file is damaged and won't open
What to do when Illustrator says an .ai file is damaged, how modern .ai files relate to PDF, and how to repair the file structure in your browser.
Data and config files
CSV, JSON, XML, YAML, calendar and SQL files that fail to import.
- CSV opens with everything in one column (wrong delimiter)
Why a CSV shows all its data in a single column in Excel, how to import it correctly for free, and how to re-save it with the right delimiter in your browser.
- CSV shows garbled characters: "é", "’" instead of é and ’ (mojibake)
Why accented letters in a CSV turn into é or ’, how to open the file as UTF-8 for free, and how to repair double-encoded text in your browser.
- JSON error: "Unexpected token" or "expected ',' or '}'"
Why JSON.parse fails with "Unexpected token" or "Expected double-quoted property name", the usual mistakes to check, and a browser tool that repairs them.
- XML parsing error: "not well-formed", "opening and ending tag mismatch"
What XML "not well-formed" and "opening and ending tag mismatch" errors mean, how to find the mistake, and how to repair broken XML in your browser.
- YAML error: "mapping values are not allowed here" or tabs and indentation problems
Why YAML fails with "mapping values are not allowed here" or on tabs, what to check first, and how to normalise indentation in your browser.
- Calendar (.ics) import failed or the file is not a valid iCalendar
Why Google Calendar, Outlook or Apple Calendar rejects an .ics file, what is usually wrong with it, and how to repair it in your browser.
- SQL dump import fails: "You have an error in your SQL syntax" (MySQL error 1064)
Why importing a .sql dump fails with a syntax error, how to find the broken statement, and how to repair missing semicolons and brackets in your browser.
- Excel drops leading zeros and turns long numbers into 1.23E+15 when opening a CSV
Why Excel strips leading zeros and turns long IDs into scientific notation when it opens a CSV, how to import as text for free, and how to build a clean .xlsx in your browser.
- Combine several CSV files into one when the columns don't match
How to merge several CSV files whose columns are in a different order or don't all match, using free methods first and a browser tool that lines columns up by name.
- Remove duplicate rows from a CSV file
How to remove duplicate rows from a CSV, by whole row or by chosen key columns, with Excel and Google Sheets steps and a browser tool that keeps the original order.
- CSV import fails or data shifts because some rows have too many or too few columns
Why some rows in a CSV have more or fewer columns than the header, how to find them, and how to repair the file so an import doesn't silently corrupt your data.
- Convert a fixed-width or mainframe text file to CSV
How to turn a fixed-width report or mainframe-style record file into a clean CSV: free Excel steps, and browser tools that detect columns or use your field widths.
- Blank cells after exporting a sheet with merged cells (only the first row has the value)
Why merged cells turn into blank rows in a CSV or import, how to fill them down for free in Excel and Sheets, and a browser tool that fills them for you.
- Contacts (.vcf / vCard) won't import into Google, iPhone or Outlook
Why a .vcf contacts file fails to import (unclosed cards, missing name, broken lines, garbled names) and a browser tool that repairs it.
- Recurring events wrong or rejected in a calendar import (RRULE errors)
Why recurring calendar events import wrongly (bad RRULE, UNTIL and COUNT together, wrong day names) and a browser tool that repairs them.
Websites, servers and developer files
Sitemaps, robots.txt, server configs, feeds and other files behind a website.
- .htaccess causes a 500 Internal Server Error
How to find the line in .htaccess that causes a 500 error, the usual mistakes (unclosed blocks, misspelled directives, bad rewrites) and a browser tool that repairs them.
- nginx: configuration test failed (unexpected "}", missing ";")
What nginx -t errors like "unexpected end of file, expecting ;" or "unexpected }" mean, how to find the mistake, and a browser tool that fixes missing semicolons and braces.
- docker-compose YAML errors: "mapping values are not allowed", ports read as numbers
Common docker-compose.yml errors (mapping values not allowed, tabs, ports like 22:22 read as a number) and a browser tool that repairs indentation and quotes port mappings.
- .env file not loading: values with spaces, inline comments and duplicate keys
Why a .env file loads wrong values or fails to parse (spaces around =, unquoted spaces, inline comments, duplicate keys) and a browser tool that tidies it.
- Google Search Console: "Sitemap could not be read" or invalid URLs in a sitemap.xml
Why Google can't read a sitemap.xml (invalid URLs, unescaped ampersands, more than 50,000 URLs) and a browser tool that cleans and splits it.
- robots.txt errors: misspelled directives, rules before User-agent, blocked pages
Common robots.txt mistakes (Useragent, Dissallow, rules before any User-agent, relative Sitemap paths, Allow/Disallow conflicts) and a browser tool that repairs them.
- Podcast RSS feed rejected: invalid dates, enclosure and iTunes tag errors
Why Apple Podcasts and other directories reject a podcast RSS feed (bad dates, missing enclosure details, guid, iTunes tags) and a browser tool that repairs them.
- WordPress import error: "This does not appear to be a WXR file" or invalid XML
Why the WordPress importer rejects an export file (missing WXR version, invalid XML, unescaped characters) and a browser tool that repairs it.
- Postman: collection import failed or "format not recognized"
Why Postman won't import a collection file (invalid JSON, wrong schema, headers as objects) and a browser tool that repairs the common mistakes.
- "Invalid regular expression": nothing to repeat, unterminated group, bad range
What the common regular-expression errors mean (nothing to repeat, unterminated group, range out of order), how to find the fault, and a browser tool that repairs patterns.
Accounting, shop and trade files
Bank statements, QuickBooks, product CSVs, crypto exports and EDI.
- Bank statement CSV or OFX won't import into your accounting software
Why accounting software rejects a bank statement export (date formats, amount signs, separate debit and credit columns, broken OFX) and a browser tool that normalises it.
- QuickBooks IIF or QBO import error: transactions don't balance, wrong format
Why QuickBooks rejects an IIF or QBO/OFX file (rows not matching the header, missing ENDTRNS, wrong dates, unbalanced splits) and a browser tool that repairs them.
- Shopify or WooCommerce product CSV import fails or garbles products
Why a product CSV import fails (wrong column headers, missing required columns, duplicate SKUs, bad prices) and a browser tool that repairs it for Shopify or WooCommerce.
- Crypto exchange CSV fails to import into Koinly or another tax tool
Why a crypto tax tool rejects an exchange CSV (unsupported columns, schema mismatch, mixed exports) and browser tools that map exports to a generic import format.
- EDI file rejected by a trading partner (X12 / EDIFACT control totals, ISA errors)
Why an EDI file is rejected (wrong segment counts, missing SE/GE/IEA, malformed ISA header, segments split across lines) and a browser tool that repairs the envelope.
Privacy and file safety
Hidden personal data, fake file extensions and unsafe images.
- Is an SVG safe to upload or embed? Remove scripts and event handlers
Why an SVG can carry scripts, how to check one for free, and how to strip script blocks, event handlers and javascript: links in your browser.
- Remove hidden personal data (GPS, author, revision history) from photos, PDFs and Office files
What hidden metadata files carry (camera, GPS location, author names, revision history), how to check and remove it for free, and a browser tool that lists and strips it.
- Is this file really a PDF or image? Check for a fake or double file extension
How to tell whether a file is really what its name says (fake and double extensions, hidden archives), and a browser tool that reads its real type without uploading it.