The m2550pup.dll file is part of the Konica Minolta Proc PCLXL Unicode (PROCU_DLL) module. This is part of a process module for a printer driver from Konica Minolta. Konica Minolta makes hardware that works with computers, including printers.
This file is part of the program that tells your computer how to send information to those printers. If you get an error with this file your printer may not work as expected. One way to fix such an error is to reinstall the driver files for the printer.
However, dll errors usually are related to the Windows registry. The registry is a database of all the pieces of every program installed on your computer. Dll errors are caused when the information in the registry does not match the reality on your machine.
ZookaWare PC Cleaner is a registry cleaner. ZookaWare PC Cleaner finds and fixes all the errors in your registry, including errors with driver dlls. Instead of doing a complete reinstall, just run ZookaWare PC Cleaner.