Please make sure the driver is loaded correctly for the printer. Test printing to the printer from a different application, like Notepad.
If the issue persists, download and extract http://dl.waspbarcode.com/wasp/supportfiles/ListPrinters.zip and run PrinterWMI.bat. Send us the PrinterWMI.txt it creates and let us know the name of the printer you are attempting to use.
If you have not already sent the log files, please send those as well by following these instructions:
Download and run WaspSupportUtility.exe fromhttp://dl.waspbarcode.com/wasp/WaspSupportUtility.exe
Close Labeler if it is currently open. Open the WaspSupportUtility and on the Log Files tab, click the button at the bottom for “Change Log Level to 0 (Verbose)”.
Reopen Labeler and recreate your error.
In the WaspSupportUtility, click Zip All Logs. Please send us the zip file it produces, along with the label file you are working with that produces the error.