When adding a network printer to a Windows PC (in our case Samsung X7600s by Group Policy), sometimes the printer doesn't appear, and when attempting a manual install you get Operation Failed with Error 0x00000057.
There are a lot of forum posts about this, many of which talk about mucking around with security permissions, copying folders from known good machines and that sort of shenanigans. None of this worked for me, so here's my solution. It's not actually a solution to the underlying problem, but it is a reasonable workround for the symptoms.
On the offending PC, go to Devices & Printers and go through the Add New Printer process to add a local printer. It doesn't matter about ports because you're going to delete it straight away. Use the 'Have Disk' option and point to the correct driver. If you're asked about driver versions, choose to Replace the Current Driver.
Once the install has finished, delete the printer entry you've just created, then try adding the network machine again. Boom.