PUP.Optional.Reimage is the detection name for Reimage Repair, Reimage Plus, and Reimage Protector, which are known system optimizer PUPs. It is offered in various ways, but usually as an online computer repair tool.
Common Infection Method
PUP.Optional.Reimage comes in many forms. More commonly, they can be found in bundlers and are known to use aggressive and misleading advertising.
Malwarebytes Anti-Malware completely removes this threat, unless specifically pointed out in a dedicated removal guide. No further clean up is required.
An example of a removal guide for Reimage Repair can be found on our forums.