PDP authentication failure: What it is, and how to fix it

What is PDP authentication, and why is it important?

PDP is an abbreviation for packet data protocol. A protocol is a set of rules that computers need to follow. Packet delivery protocol is an important protocol because it helps you facilitate data transfer over mobile networks. 

Packet data protocol authentication is the process your phone or tablet uses to connect to a mobile network. When a mobile device tries to establish a data connection with a mobile network, the network asks for information. Typically, this information includes its IP addresses and international mobile subscriber identity (IMSI) number. The network has to receive and authenticate this information to let a device access it.

You can think of authentication as someone knocking on the door of your clubhouse and asking them for their identity and password. Without these details, you won’t let them in, right? In the same way, a network won’t let a device connect without PDP authentication.

What does PDP authentication failure mean?

PDP authentication failure means that the PDP authentication we just talked about didn’t work properly. This means that your device didn’t send the network the right information or that the network didn’t receive the information correctly. Either way, your device isn’t able to connect to its mobile network. You won’t be able to access data services or use the internet unless you connect to Wi-Fi or use a friend’s mobile hotspot. 

What causes PDP authentication failure?

Though nothing with the device seems to have changed, your phone or tablet is suddenly not working as it should. You can’t connect to your cellular network and have no data for surfing, scrolling, and streaming. What happened? Possibilities include::

• SIM card issues: If you use a physical SIM card, it may not be inserted in its slot properly. There could also be dirt, dust, oil, or other build-up on it preventing physical connection. A new SIM card may also be damaged or incompatible with your device.

• eSIM problems: What is an eSIM? It’s a built-in programmable SIM card in your device. If you’ve recently started using one and now you can’t access your data services, the eSIM could be flawed or incorrectly configured. If you use an eSIM with a physical SIM, it’s possible that your phone is getting confused between the two and sending incorrect signals to your network. Some carriers may not support eSIMs, which can cause an authentication failure.

• Account issues: You may have an account or subscription that you need a username and password for. If you do not enter these correctly, a failure could occur.

• Data plan problems: If your data plan is expired or you’ve already used up all the data allowance in your plan, you might get a failure notice.

• Software problems: The software your phone or tablet uses might have bugs or glitches in it. It might also be out of date and, therefore, considered unsafe, so your cellular network provider may not allow it to connect.

• Incorrect settings: The network settings on your device may be incorrect. Most commonly, the APN (access point name) settings may be wrong or missing entirely. Since the APN is like a gateway between your mobile device and the internet, it needs to be set up correctly, or PDP authentication failure will occur.

• Network issues: It may not be a problem with your device at all. Your cellular network may be temporarily unavailable. It could also be encountering high network congestion, which could dramatically slow down device authentication and may result in failure messages instead.

How to solve PDP authentication failure

If solving PDP authentication failures sounds like a technical nightmare, it’s not time to smash your phone to pieces just yet. Your device, SIM, eSIM, or even the network might be causing the issue. Chances are good, though, that it’s only a minor issue. Here are some of the best ways to solve PDP authentication failure:

• Check your reception: Take a peek at how many bars you have. If you’re down to just one or none, or if the number of bars keeps changing, you may have poor network coverage where you are. If that’s the case, you’ll have to move to a place with better reception and try again.

• Try airplane mode: The easiest fix by far is to turn off all of your connections by entering airplane mode. Leave your device in this mode for at least 10-15 seconds before turning it off and trying your data connection again.

• Restart your device: If your phone or tablet is experiencing a temporary glitch, a hard restart may help sort it out. Hold your power button down until you’re asked to confirm the shutdown. Wait until the screen goes completely black, and then wait a couple more minutes before restarting and trying your data connection again.

• Check your account status: Have you paid your phone bill? Have you used up all the data in your package for this month? Download your eSIM app or other service app, check your bill payments, or call your carrier to check if everything is in order with your account.

Didn’t work? Try these moderately difficulty fixes:

• Check your SIM: Use a SIM removal tool or a safe alternative to remove the SIM card from your phone. Check for videos online with instructions for your specific phone model if you’ve never tried it before. It’s possible your SIM was inserted incorrectly or is dirty. Try gently cleaning it and trying again, or try another SIM instead. If the new SIM works, it was a problem with your other SIM, so it may be a good idea to check if the SIM card went bad.

• Update your software: If you’re running an out-of-date operating system on your device, find a Wi-Fi connection to connect to. 

  • On an iPhone, go to “Settings” > “General” > “Software update.”

  • On an Android device, go to “Settings” > “About phone” > “Check for updates.”

Still having problems?

• Reset your network settings: You may have a network setting configuration problem. Try to reset network settings as follows: 

  • To reset network settings on an iPhone, go to “Settings” > “General” > “Transfer or reset iPhone” > “Reset network settings.” 

  • To reset network settings on an Android device, go to “Settings” > “System” > “Advanced” > “Reset options” > “Reset network” or “Reset Wi-Fi, mobile & Bluetooth.” 

• Reset your APN settings: Check that your APN settings are correct by looking on your carrier’s website or contacting it directly. Here’s what you need to do depending on your device:

  • On an iPhone, go to “Settings” > “Cellular” > “Cellular data network” or “Settings” > “Mobile data” > “Mobile data options” > “Mobile data network.” 

  • On an Android device, go to “Settings” > “Network & internet” (or “Connections”) > “Mobile network” > “APN settings.”

What to do if you can't solve PDP authentication failure

Did you try everything on our list of fixes, from easy to tricky? If you did and nothing worked, it’s time to contact your mobile service provider. If you can visit the company in person with your device, its customer support will  have the best chance of solving your problem. If not, remote support representatives will still be able to troubleshoot the problem and help you out. They may need to check the network settings on their end or reset your connection to return your internet connectivity. In any case, they should be able to provide you with expert attention and solve your PDP authentication failure issue. 

How to avoid PDP authentication failure

The best way to fix PDP authentication failure is to never have one in the first place. Here are some steps you can take to help make sure this problem doesn’t happen:

• Update regularly: PDP authentication might occur if your software is buggy or out of date. If you keep your system updated regularly, you should avoid compatibility and security issues with your mobile service provider.

• Confirm your eSIM compatibility: Before you even think about setting up an eSIM, ask yourself, “Is my phone eSIM compatible?” If your phone can’t handle this technology because it’s too old or running outdated software, you will have problems. You should also be able to answer the question, “How long does it take to activate an eSIM?” Whether you’re using an eSIM in the USA or anywhere else, it may take time to activate, and this could limit your internet access.

• Get expert help: Whether you’re struggling with a new SIM, eSIM, or just your network settings, get support from your carrier so that you don’t face connectivity issues in the future.