i still have the same problem with adobe reader x.
the font "code128" is installed in windows 7 pro correctly, the used user ist still administrator.
if i open an existing document with barcodes in it it will only display other things like numbers or signs, if i try to open this document with "another" reader for pdfs the barcodes is correctly shown.
the document prosperties of the pdf-file in adobe reader shows the font code 128 but it seems that it will be replaced by adobe sans mm.
Why don't you embed the font when you create the PDF?
I cant. I got these documents from our distributors or from other customers. Maybe i could please them to make these documents correctly for displaying in the reader. but thats not the problem. also viewing or printing these documents with another open-source reader e.g is an acceptable solution.
i still searched a while for a solution cause i thought it could only be a little problem. but i didnt find anything except that it has something to do with the creation of the document as you said.
i only wants to know if there is no solution why making an pdf unreadable for the reader....