troubleshooting guide
Fix can you trim, fold or tape over a shipping label without causing scan problems?. Check scale, paper size, margins, orientation and barcode whitespace before reprinting.
Best next step
Start with the tool or template that matches this guide before printing paid postage again.
Last reviewed: 2026-06-15
Trim only unused outer paper when every barcode, quiet zone, address and service mark stays intact. Keep the barcode flat and off seams or edges, and do not cover it with tape. If the active label cannot fit without folding or repair, reprint in the correct format.
Symptom-led fix
Follow the symptom that best matches your bad print. Each step points to the safest next tool before you buy postage again.
A full Letter or A4 page is being fitted onto one 4×6 thermal label.
Inspect the PDF page box. Get the issuer's 4×6 format or extract only a complete label area; do not enlarge the miniature output.
Inspect the PDF pageA true 4×6 source prints proportionally smaller on matching 4×6 media.
Confirm 4×6 in the driver, disable Fit, print one blank template, then calculate a correction only if the media path already matches.
Measure the scale errorThe label boundary is correct, but fine lines are fuzzy, gray or broken.
Treat this as print quality, not page scale. Test density, speed, media and printhead condition before another live label.
Run a print-quality testRemoving blank sheet paper is different from cutting the label itself. Stop before any barcode whitespace, tracking number, address, service text, routing mark or border used by the issuing workflow. When you cannot identify those boundaries, reprint instead of trimming.
FedEx advises placing the label on the package's largest surface and avoiding seams or edges because wrinkles can cause scanning problems. If the package shape makes that impossible, follow the carrier's current placement instructions or use an appropriate pouch or tag.
USPS and FedEx both publish warnings against tape over barcodes; FedEx specifically notes reflection from clear tape. Tape only the surrounding paper when the issuing instructions allow it, or use a label pouch that keeps the barcode unobstructed.
Do not stretch, compress, redraw, photograph or patch a barcode. Return to the original PDF, match its page size to the printer media, and print at 100% / Actual Size. Treat a clean reprint as the default when active content was cropped, folded, wet, blurred or covered.
This page is a practical print-setting checklist, not official carrier policy or a promise that a label will be accepted.
Confirm the current format in your platform or carrier account, keep the original PDF, and stop if a test print is cropped, blurred or incorrectly scaled.
Troubleshooting advice is general. Record the printer model, paper size, PDF viewer and scale setting so you can verify each change.
Yes only when it is clearly outside every active label element and required quiet zone. Do not cut into routing, address or barcode areas.
Keep the barcode flat. FedEx warns that seams and edges can wrinkle a barcode and cause scanning problems.
No. USPS and FedEx instructions warn against tape over barcodes, including clear tape that can reflect scanner light.
Use the carrier's current placement guidance or reprint in a format that fits. Do not improvise across scan-critical content.
Reprint when a barcode, quiet zone, address, service mark or tracking number is cut, distorted, blurred, folded or covered.
Understand barcode risk before drop-off.
Check seven scan-critical items before handoff.
Check paper, scale and orientation before printing.
Download a blank 4×6 shipping label template.
Fix tiny labels, scaling problems and bad print settings.