I strongly suggest that you standardize your printer settings across the network but do not attempt to do this by using shared printers. Merely setting to the windows default printer will not give you the flexibility to print different forms on different printers depending on your work flow. Using shared printers or UNC names will cause this exact error.
1. Manually define all printers needed using the same local printer name on all workstations and the SL application servers.
2. Use all capitol letters on the local printer names
3. In Order Management, Order Types, Set the Output Device to the new standardized name.
This will fix this problem.
Andy