added note in readme about needing to change permissions of .netrc file to address issue #152

Author: avvalenx

CHANGELOG.md

@@ -8,6 +8,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 ### Added
 - Added error messages to inform user if .harmony file is formatted incorrectly or missing a key
 - Added error message if .netrc file is not found and prompt for Earthdata login credentials to create a .netrc in the user's home directory
+- Added note about how to change permission of .netrc file for mac and linux
 ### Changed
 
 ## [1.15.2]

README.md

@@ -91,7 +91,9 @@ machine urs.earthdata.nasa.gov
     password podaacIsAwesome
 ```
 
-**If the script cannot find the netrc file, you will be prompted to enter the username and password and the script wont be able to generate the CMR token**
+**If the script cannot find the netrc file, you will be prompted to enter the username and password to create one automatically. Without a netrc file the script won't be able to generate the CMR token**
+
+**If using MacOS or Linux you will need to change the permissions of the netrc file by running chmod og-rw .netrc**
 
 
 ## Advanced Usage