| Problem | Most Likely Cause | Solution | | :--- | :--- | :--- | | Scanner reads nothing | Missing start/stop asterisks | Add * before and after data. | | Lowercase scans as uppercase | Using Standard Code 39 font, not Extended | Download genuine 3 of 9 Extended font. | | Scanner reads gibberish (e.g., +A+B+C for "abc") | Scanner is in Standard mode, but your font is extended. The scanner sees the shift sequences as literal data. | Enable "Full ASCII" mode on your scanner (scan setup barcode from manual). | | Barcode is extremely long | Extended mode doubles length | Reduce font size or switch to Code 128 for dense data. | | Barcode prints but has gaps | The font is not installed correctly; printer substituted a default font | Reinstall font, restart application, print as image. |
: Like standard Code 39, it requires an asterisk ( * ) at the beginning and end of the data string for a scanner to recognize it (e.g., *DATA* ). Usage and Installation
If you type this string into a word processor and apply a Code 39 barcode font, the result will be problematic. Standard Code 39 does not have a glyph for lowercase letters. Depending on the font design, the barcode might encode JOHN.DOE@EXAMPLE.COM (uppercase), or it might omit the characters entirely, resulting in unreadable data.
: By using combinations of two standard Code 39 characters to represent special symbols or lowercase letters, it can encode any character found on a standard keyboard.
If you are looking for specific font files to download or select, popular options include: Free Barcode Font - Code 39 True Type - Barcodesinc.com