Plunge Mill under ledge

[#1]

Alright guys I am trying to use the plunge mill operation under the ledge pointed out with the green arrow, any suggestions? I haven't used the pluge mill option very much but I can not get anything to work. I will be done with a right angle head and extended tooling, I have got it to work when the ledge is in the opposite orientation but this part is to tall so we have to do it while the part is upside down.

Any tips?

Thanks TJ

[#2]

I keep getting the following error

"Put to grid attempted on out of range coordinate"

[#3]

Use check geometry from the analysis menu, since this error only occurs if the geometry is bad.

Check for face and solid problems.

[#4]

What is your tool axis?

FYI the geometry and cut level definition should be the same as Cavity Milling.