Stanford (and probably many other schools) provide official transcripts in the form of a signed PDF. This transcript can only be opened using Adobe Acrobat; other readers simply choke on the document and can't open it. This is caused by the use of a proprietary "secured" document signing feature, apparently exclusive to Adobe Reader, which verifies the authenticity of the transcript. (For comparison, Duke University provides regular PDFs that can be opened by any reader, but can be verified by uploading the file to a trusted authority who confirms the document's legitimacy.)

Stanford's PDFs are particularly annoying because you can't take a screenshot with Print Screen (though the Snipping Tool works), Acrobat won't remove the signature, and attempting to use Acrobat Reader print the PDF to CutePDF simply results in a mostly-blank page with the following text:

ERROR: undefined
OFFENDING COMMAND: get
STACK:
/quit
-dictionary-
-mark

Here's how to un-certify the PDF:

1. Open the secured PDF in Acrobat Reader and "Print to File" (File/Print, click Advanced, and check the box).

2. Note: this step may violate certain laws. Proceed at your own risk. A comment in the file declares that "Removing the following eleven lines is illegal, subject to the Digital Copyright Act of 1998."

   Open the resulting .ps file in a text editor. Find and delete the following block:

   mark currentfile eexec
   ... stuff here ...
   cleartomark

   Then, use ps2pdf or similar to convert the PostScript file to PDF.

   This entire step can be accomplished with the following:

   $ sed '/mark currentfile eexec/,/cleartomark/d' secured.ps \
         | ps2pdf - unsecured.pdf

3. For Stanford transcripts, the pages need to be rotated clockwise, so use pdftk:

   $ pdftk input.pdf cat 1-endE output output.pdf