Ever since I went digital-only by getting rid of my traditional telecom provider (France telecom here in France) I basically lost the ability to send classical fax. But that’s OK because I need this service very rarely and only because some institutions here are not tech savvy enough to receive the scanned copies by email.

On the other hand my ISP (Free) has recently introduced a new “virtual” fax service for its subscribers. You upload a PDF file through a web form, type in the phone number of the recipient and they get a fax from you. There is a special number derived from your phone number that acts as an originating fax. If somebody sends you a fax back, you’ll get it via email as a PDF attachment.

In theory, all this sounds great. In practice, there was a very irritating problem I ran into. To send some documents, I used my newly purchased Cannon MP600 to scan them straight into PDF files. I verified that the file is nicely readable in Acrobat Reader, but when I tried to send it, instead of email confirmation I got back a message from Free fax service complaining that PDF format cannot be recognized.

It turns out that the PDF produced by Cannon MP600 is a PDF version 1.3 which for some reason Free’s software cannot read. The solution was ridiculously stupid: I “printed” the very same PDF into PDF through a virtual printer driver, producing essentially the same thing but in PDF version 1.4, which worked fine (go figure).

Why would Free reject older, more compatible PDF format in favor of newer is beyond me.