Lukai wrote:
The error you're seeing isn't a memory card issue, its an issue with your phone not recognizing your SIM card. The issue is either with the card (someone touched the contacts) or the contacts on the device itself(unlikely).
What I would suggest is to open the back of your phone, take out the SIM card, make sure both the card and the device contacts are clean, and re-insert the card.
Holy smokes! My heart goes out to anyone that ever has to remove the back panel of a DROID 4 and then attempt to successfully put it back on! 
Hmmm, and I thought I was the only one who's been having this problem. As many other ppl in this discussion, my problems started around june-july timeframe. I put up with it all summer and finally had about enough of my 4G (which was excellent from March until June/July) dropping, then swtiching to 3G, then dropping out completely and cycling like that the whole time I'm in my house. As mentioned, from March until the beginning of summer 4G never dropped below 3 bars... I did speed tests, jitter, reliability test and all supported my intentions of ditching my cable internet and paying Verizon to use my phones 4G as a hotspot in my home. Needless to say, I can't do this anymore. Heck, I can't even use my phone to browse the internet without waiting every minute or so for my darn connection to decide it's going to work. Needless to say, this really gets under my skin. I spend a majority of the day in my home and I can't even use my phone for what I bought it for. REDICULOUS.
So, I call verizon and share with them what I'm experiencing. Their first response.... Replace the phone. So, they send me out a factory refurbished phone. Now, I have to figure out how to transfer all my apps, contacts, and other app data over to my new phone.... (not easy, if you're ever done it). So, I ended up paying the price for a robust backup app, which didn't end up transferring everything I needed it to. Hours of time spent doing this, just to find out this phone is doing the same thing as my old phone. sigh.... I'm excersing my patience at this point... A LOT.
I call Verizon back to explain to them that I'm still having an issue. Their response; We'll put a trouble ticket in and have someone check the network in your area to verify if their are any problems. Ok, I think to myself, "We might actually be getting somewhere". The gentleman on the phone also informs me that I might not be receiving a signal in my home because sometimes it's hard for the signal to penetrate through walls. That's when I inform him (again), that my 4G was stellar from march (when I bought the phone) until June/July. No comment from him about this other than he said it's a possibility there have been issues with the towers and the trouble ticket would address any issues with the towers.
Two weeks go by and I receive a call from a gentleman from Verizon who informs me they did find an issue with one of the towers in my area and that I should be receiving a better signal in my home... I inform him that there hasn't been any change in signal strength inside my home. He asks if I power cycled my phone recently, I answer with "yes, just an hour ago". His answer was that if that didn't solve the problem, then I would just have to "buy" a network extender. I literally laughed out loud.. (LOL). BUY a network extender??? Wait, aren't I already paying you for your services, which you clearly aren't providing to me??? He quickly puts me on hold, speaks to his manager and offers to let me have the network extender at no cost. I start asking questions about how the network extender works and soon find out, it's only going to provide 3G coverage..... NOT 4G. At this point, I just want reliable service, so I accept the offer.
I receive the network extender in the mail about a week later. I set it up, trying first the internal GPS, but it will not locate a satellite and will not continue with the inital boot up process. So, I run the external GPS out to a window and try power cycling it that way. Nope... Still will not initalize. After trying this a few more times, I'm thinking maybe it has something to do with the router I have it plugged into. So, I call verizon and discuss the issue I'm having with them. Their solution; I need to have above 80% quality of signal for VoIP to work. We run a test using a specific website they give me and determine my quality of service is way too low (40-50%). Alright, so I think I'm getting somewhere.... I call my internet provider (TW) and discuss with them what I'm trying to do and the test's I've run. Needless to say the lady on the other end of the line had no idea what I was talking about and refused to acknowledge there was an issue with quality of service. After a good 45-60 mins on the phone with her going around in circles, I ask to speak to a manager. The manager comes on the line and refers me to a level 3 technician. After waiting another 30 minutes or so more, I finally speak with said level 3 technician.... I run him through the tests I've done and what I'm trying to do. He claims there's an issue with my router and "I" need to fix it.... I'm thinking to myself at this point... All this for a service I did get 4 months prior...
So, after playing around with the settings in my router and much time searching the internet for any similar problems, I realize there's a setting in my router which had been set from the manufacturer. Off hand I want to say it has something to do with port blasting. So, I uncheck this and re-run the tests for quality of signal. It worked, zero packet loss, 80-100% quality of signal. I'm thinking, this is it... I found the problem. So, I turn on the network extender and go through all the rigger-ma-role I did before with the GPS antenna. Waited a couple hours and found it still wasn't initalizing...
I gave up.... I'm sitting here in my house right now as I write this watching my signal status hop from 2 bars of 4G to 3G to no signal at all... again and again. Tell me Verizon, do you think you're providing me with the service I'm paying for? I could understand if I was the only person having this issue, I could understand if I never had a good signal in my house to begin with, but I will tell you this... If I would have know I would be going through what I'm going through right now with your service, I would have ended my 10 yr reign with you guys and found a carrier that actually provides service to their customers. It's not like I'm out in the country, I'm still within the Rochester, NY city limits. 14624 to be exact. I will be switching to another carrier, if this problem is not resolved soon. and I will be fighting tooth and nail to get out of my contract without paying the early termination fee 