# PDF Repair Corrupt Attempt to repair damaged PDF headers and broken/missing XRef tables > Canonical page: https://elysiatools.com/en/tools/pdf-repair-corrupt - **Category:** PDF Tools - **Keywords:** pdf, repair, corrupt, xref, recover, qpdf ## Overview Attempt practical recovery of partially-corrupt PDF files. **Repair strategies:** 1. Header normalization (recover misplaced or missing %PDF- header) 2. qpdf rebuild (object table and xref reconstruction) 3. pdf-lib rewrite fallback for mildly damaged structure 4. Ghostscript rewrite fallback Not all severely corrupted files are recoverable. ## Inputs - **Source PDF File** (file): Upload potentially damaged PDF ## When to use - When you receive a 'File is damaged or could not be repaired' error message. - When a PDF file fails to open due to a missing or corrupted cross-reference (XRef) table. - When a file header is malformed or missing the standard '%PDF-' identifier. ## How it works - Upload your damaged PDF file to the tool. - The system attempts to normalize the file header and reconstruct the object table. - If the initial repair fails, the tool automatically applies secondary recovery methods using pdf-lib or Ghostscript. - Download the reconstructed PDF file once the recovery process is complete. ## Use cases - Recovering important documents that were interrupted during a download or transfer. - Fixing PDF files that were partially overwritten or corrupted by storage media errors. - Restoring access to legacy PDF files that have developed structural inconsistencies over time. ## Frequently asked questions ### Can this tool fix all corrupted PDF files? No. While the tool is effective for structural issues like broken XRef tables or header errors, it cannot recover data from files that are severely encrypted or physically missing data. ### Is my data secure during the repair process? Yes, your files are processed in a secure environment and are not stored permanently on our servers. ### What is an XRef table? The XRef table is a critical component of a PDF that acts as an index, telling the PDF reader where each object is located within the file. ### Does the tool modify the original file? No, the tool creates a new, repaired version of your file, leaving your original source file untouched. ### Are there file size limits? 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