If you are using more than one computer with the uniFLOW client (for multiple PTAs) then you'll need to follow these steps on your Windows computer(s) to allow the uniFLOW pop-up to display on the proper computer. You do not have to follow these steps on Mac OSX.
1) Remove the original CanonMFD print queues from Devices and Printers.
2) Programs and Features> Turn Windows features on or off> Print and Document Services> (Check the box for) LPR Port Monitor.
3) Devices and Printers> Add local printer> Create a new port> LPR Port> Next
Name or address of server providing lpd: seq-uniflow
Name of printer or print queue on that server: CanonMFD-Secure-LPR
4) When the wizard asks for the driver select 'Have disk' and navigate to:
Windows 32-bit OS: \\seq-uniflow\Installers\CanonDrivers\PS3_v20.85_INF
Windows 64-bit OS: \\seq-uniflow\Installers\CanonDrivers\PS3_v20.85_Setup_x64\Driver
Then select Canon iR-ADV C5045/5051 PS3 from the list.
5a) Open 'regedit' and navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Nt-ware\Mom\MomClient. Change UserName key value from %u to %u-%i
5b) Alternatively download the attached file and open it on the machine to automatically adjust the registry entry.
6) Restart uniFLOW client.
7) Perform these steps on all Windows computers that will be used with uniFLOW. Once configured the uniFLOW client popup should occur only on the computer that sent the print job.