Sunday, November 16, 2025

How to read/view a damage/corrupt PDF file


Sometimes PDF files can get scrambled and you are stuck not being able to open a PDF file. Most PDF software cannot open the test file below. Adobe Acrobat Reader issues the pop-up screen could not open because it's not a supported file type or the file has been damaged.




Solution: 



Get XpdfReader PDF software which can open limited malformed PDF files!

Also XPDFReader does not implement the Adobe JavaScript engine required for interactive features like calculations, validations, or dynamic field updates, make it safer option.


For more information about internal structure of PDFs




Test 1:

In the following sample file, the file starts with malformed PDF file signature 


%P!F- which is incorrect and should be %PDF-, as seen in FRHED editor. 

XpdfReader is the only app I came across that could open this file with this first malformed change.

Test 2: 
 
Then I remove leading angle bracket < where there should be two for <<Lineralired, and it opened! 

Source

The original unadulterated file header is

%PDF-1.5%<bh:e2><bh:e3><bh:cf><bh:d3>10 0 obj\<</Linearized 1/L 105981/O 12/E 101484/N 1/T 105677/H [ 502 173]>>endobj

Opened Malformed File
























































For more information about internal structure of PDFs

Example of absolute minimal PDF file contents "Hello World", copy and pasted into FHRED.

%PDF-1.1
1 0 obj
<< /Type /Catalog /Pages 2 0 R >>
endobj
2 0 obj
<< /Type /Pages /Kids [3 0 R] /Count 1 >>
endobj
3 0 obj
<< /Type /Page /Parent 2 0 R /MediaBox [0 0 200 200] /Contents 4 0 R /Resources << /Font << /F1 5 0 R >> >> >>
endobj
4 0 obj
<< /Length 44 >>
stream
BT
/F1 12 Tf
72 100 Td
(Hello World) Tj
ET
endstream
endobj
5 0 obj
<< /Type /Font /Subtype /Type1 /BaseFont /Helvetica >>
endobj
xref
0 6
0000000000 65535 f 
0000000009 00000 n 
0000000056 00000 n 
0000000107 00000 n 
0000000212 00000 n 
0000000310 00000 n 
trailer
<< /Size 6 /Root 1 0 R >>
startxref
380
%%EOF


Here's Hello World.pdf opened in XpdfReader 4.06


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