Dymo Labelwriter 450 Troubleshooting & Printing Guide This is the big momma of all Dymo printing errors, as it is a very common complaint. Here are the steps for unjamming a jammed LabelWriter 450. Unplug the printer. Open the cover. Cut off the intact labels. Pull out the front panel, which is the part that bears the "LabelWriter 450" sign. This will reveal a lever and the label feed guide.