After reading this thread on how to remove the severe weather alerts, I took it upon myself to find a way to remove Presidential Alerts, which is not an option in the stock ROM. Sure enough, I found the preferences file that the stock messaging app uses, changed a Boolean value, and profited.
What I used:
- External SD card installed in the phone.
- File explorer with root capability (ES File Explorer in my case; I'm sure Root Explorer works just as well).
- PC with a Text Editor (Wordpad worked best for me). I had seen posts on other threads (don't remember exactly which ones) that stated using text editors on the phone may not be saving files properly, so I went with the tried and true route.
Here are the steps that I used, based on memory. (Assuming root capability is already enabled on the file explorer.) Apologies if I left anything out, since it's been a few days since I did this on my phone.
1. Open the file explorer and navigate to the directory /data/data/com.android.mms/shared_prefs
2. Make a copy of the file com.android.mms_preferences.xml and save that copy to the root of the external SD card.
3. Rename the original file to com.android.mms_preferences.xml.orig. This is backup of the original XML file just in case something goes wrong along the way.
4. Connect the external SD card to the PC by whatever means. (I unmounted/removed the external SD card, and inserted it into a card reader attached to the PC.)
5. Navigate to the disk drive corresponding to the external SD card.
6. Using the text editor, open the file com.android.mms_preferences.xml.
7. Search for the Boolean name #cmas#type##presidential#enabled.
8. Change the value associated with that Boolean from true to false.
9. Save the XML file.
10. Insert the external SD card back into the phone.
11. Copy the file com.android.mms_preferences.xml from the external SD card to the directory /data/data/com.android.mms/shared_prefs (you're overwriting the XML file that's already there - that's OK)
12. Exit the file explorer.
13. Reboot the phone. (Not sure if this is really needed, but it's good practice.)
14. After rebooting, check the Messaging settings and verify that there is no check next to Presidential Alerts.
15. (Optional) If Presidential Alerts are not checked, go back into /data/data/com.android.mms/shared_prefs with the file explorer and delete "com.android.mms_preferences.xml.orig".