Assuming that the printer has two input trays, one for A4 and one for letter size.
Does the installed print driver use the correct command (pcl5?) to select the A4 tray.
I once phoned HP and asked for the commands to select the trays on a MFP printer, and they could not tell me. I had to try all of them (about 20) one a time.
Hi jgt, thanks for your answer, yes, has two trays. The PDF printed is generated on A4 paper (A4 tray) but with Letter Format, the margins are misplaced and the paper size cut the image .
The PDF in windows has a 210 x 297 dimension , A4. It's rare.
You can't send a pdf file to the printer using lpr, unless the destination print driver has the ability to convert pdf to a print stream suitable for the printer.
If your printer supports postscript, you can pipe the pdf file through pdf2ps to convert the pdf file. The bar code will still print.