I created a userform with a textbox called txtMsg and a Read button
and copied your code  into the click event for the button.
I then created the a.txt file  and tested your code
and it worked fine!!! Peter loves IP "10.11.12.13"
showed in the text  box.

Try entering a longer string like: Peter loves all IP regardless of
location
and try it.
Does it truncate?
Maybe the problem  is with the definition of the textbox on the userform.
Is there a MaxLength value set?