[Sprint Samsung Galaxy S 4 Q&A, Help & Troubleshoot] unruly1:
Problem I am trying to solve: As soon as the device boots I get the notification "preparing network" and when I try to dial a number on the stock ROM and get "Mobile Network not available"

A Nandroid restore CM11 appears to connect to the mobile network (I can dial a number but get "your account could not be validated" because the device has not been successfully activated on the network yet)

Here is how I arrived at such a dilemma.

okay, I am gonna try to format this in a way where you can skip some sections that might be a little "ranty" while still making it informational while still requesting some assistance.

A little background (feel free to skip this part) I have been rooting and ROMing phones for a few years to support my Cyanogenmod fix. I buy my phones on eBay or Craigslist, and verify I can setup a recovery, then backup the rooted Stock ROM (to activate the device and update PRL, etc.) then install the CM version of my desire and transfer over all my settings and backup files and restore them so I have had the same look and feel for the operating system of my phone for the last few years. I am on TIng (a Sprint MVNO) and have had zero problems performing these hardware upgrades from my droid, to my galaxy nexus to my second galaxy nexus, to my galaxy S3 to my second Galaxy S3 on a regular basis using their website.

Last Friday, I picked up a Galaxy S4 (running NAE) at the local Sprint store and once verified by the Sprint employee as being a clean ESN, I was set to start my process of rooting, installing recovery (I chose TWRP), then Nandroid backup of the stock ROM, then install CM 11 M6 and copy over my backup files (Titanium Backup) from my S3 and restore them, then Nandroid backup of the CM 11 install, then restore of Stock NAE ROM to activate the phone. Here is where things get a little fishy.

For awhile now, I had been always used Clockwork in the past but several comparisons score TWRP a little higher for features and functionality so I decided to use that for my recovery. It installed CM just fine and it seemed to perform Nandroid backups without any problems (or so I thought). I attempted to restore my Nandroid Stock ROM to activate the device and upon boot I saw the familiar Cyanogenmod screen. I tried it again, but same thing. No big deal, I'll find a stock rooted NAE ROM, copy it to the SD card, install using TWRP, activate, Nandroid backup, then restore my CM Nandroid backup and be up and running. I installed the Stock Rooted NAE ROM using Odin and lose my TWRP recovery so I reinstall TWRP and make a Nandroid backup of the Stock Rooted NAE ROM using TWRP. I make sure my TWRP restore can restore my CM11 Nandroid backup and it does. Okay, I should be all set. I have a nandroid backup of stock and CM11. All I need to do is restore stock, activate and I am up. I attempted to restore my Nandroid Stock ROM backup to activate the device and upon boot I saw the familiar Cyanogenmod screen for the second time. At this point, I am a little frazzled as logically this has never happened in the history of all the devices I have worked with.

I start checking the forums to see if anyone has experienced this and see nothing. I see many "how-to" guides that cover all kinds of things for the Spring GS4 that include wiping the data and cache multiple times over and over using a recovery called PHILZ.

I abandon TWRP, restore Stock Rooted NAE ROM and as far as I can tell, I am ready to begin from scratch using PHILZ. Install PHILZ recovery, install CM 11 M6 and copy over my backup files (Titanium Backup) from my S3 and restore them, then Nandroid backup of the CM 11 install, then restore of Stock NAE ROM to activate the phone. This time I am able to successfully restore a Nandroid backup of Stock rooted ROM but I am seeing a little red x and zero bars for the mobile network connectivity.

I start checking the forums to see if anyone has experienced this and see a few people that have lost mobile network connectivity and claim loading a modem using Odin is the fix. I try NAE-Modem-Only.tar using Odin and that does not improve anything. I also try loading TriForceROM5.4 having read that any TW ROM can be used to access the menu to activate a device

Now I am stuck.

There is nothing I can do to get mobile network to work on a stock ROM. As soon as the device boots I get the notification "preparing network" and when I try to dial a number on the stock ROM and get "Mobile Network not available"

A Nandroid restore CM11 appears to connect to the mobile network (I can dial a number but get "your account could not be validated" because the device has not been successfully activated on the network yet).