Outreg2 Not Working

Hi there!
I have been using the following codes.

Code:

reg y x1 x2 x3 x4, r
Outreg2 using myreg.doc, replace

However, it returns the following message:

program outreg2 already defined
(error occurred while loading Outreg2.ado)
r(110)

Could anyone please assist me?
Thanks in anticipation.