Locked Viewport scaling

Hi,

This is my first post here, I always tried my best and did anything alone. But this thing drives me crazy and i cant find the solution.

In my drawing layout nr. 2 has blocked viewports. The button on bottom right is dark grey and doesn't work. And standard "Zoom nXP" command doesn't help either.
First layout works well with scale. But I cant change plotter to HP HP7685 as our teacher wants us to. Gives some communicate with rastric drawing. 
I attach my file below. 

Please help me, this thing is killing me:)