You can use net use to see what device names are already in use.
Status Local Remote Network
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OK S: \\servername\photos Microsoft Windows Network
OK LPT2 \\servername\laser1 Microsoft Windows Network
The command completed successfully.
Use net view \\computername to see the share name of the printer.
Share name Type Used as Comment
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Laser1 Print Laser1 (1200) PCL 6
photos Disk
The command completed successfully.
In this case the share name is "Laser1" not "Laser1 (1200) PCL 6"
When mapping printers, normally you get an error message like this
C:\> net use lpt2 \\computername\printersharename
System error 85 has occurred.
The local device name is already in use.
What error number did you get?