Hi,
Please be informed that there is no way to redirect the printer connected on Desktop A to Desktop B even though they both connect to Server A by RDP. When they connect to Server A by RDP, each of them has a separate session on Server A and all their operations on the server will not interfer with each other.
Maybe you can first use "print to PDF" to save the file from Server A to Desktop B. After that, you can remote connect from Desktop B to A and copy the file to the remote session and then print it using the Desktop A's locally available USB connected printer.
Thanks,
Eleven
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