How to Fix Error Code 300016 with Diablo 3?

Some Diablo 3 users are reporting that they end up seeing the error code 300016 (There was an error) when trying to log in with their account. This issue is exclusively reported to occur on PC on multiple operating systems (Windows 7, Windows 8.1, and Windows 10).

How to Fix Error Code 300016 in Diablo 3

Although the error message accompanied with the error is not much to go on, we’ve compiled a list of potential causes that might cause this error after looking into various user reports. Here’s the list of potential culprits:

  • Ongoing server issue – The first thing you should do is make sure that you’re not dealing with a server issue that is not beyond your control. In the past, Blizzard has been the subject of many DDoS attacks that have rendered their infrastructure inaccessible for hours. To make sure that’s not the case, start by investigating the current status of Blizzard’s servers.
  • You just finished the starter edition of Diablo 3 – If you just finished the free version of Diablo III, you can expect to see the error because the game is unable to communicate with the Battle.Net store in order to take you to the checkout page of the full version. In this case, you can bypass the issue by making the purchase manually from the web version of Battle.Net.
  • Account’s password exceeds 16 characters – This is kind of s stupid oversight on Blizzard’s part, but it turns out that you can expect to see this error if your Battle.Net password exceeds 16 characters. Since the Diablo III client is only comfortable with passwords of under 16 characters, you will need to change your password accordingly if you want to play the game without issues.
  • Outdated GPU driver – Another potential culprit that might trigger this problem is a severely outdated GPU driver that makes the game impossible to render on your computer. This is known to happen with dual-GPU setups. To fix this issue, all you need to do is update your graphics card drivers to the latest version available.
  • Local Network restriction – If you’re connected to a restricted network (school, work, or public Wi-Fi), chances are the network administrator has imposed some kind of restrictions that prevent data exchangers of this magnitude. One way to bypass this restriction is to funnel your connection through a VPN tool.
  • Bad IP / TCP / DNS Data – A network inconsistency can also be the primary cause of this issue (especially if you’re only seeing this error code after playing the game for some time). Several users that were facing the same issue have confirmed that the problem was finally resolved after they used an elevated Command prompt to release the current DNS range and flush the IP configuration.

Now that you know every potential culprit that might be responsible for the apparition of this error, here’s a list of methods that other affected users have successfully used to fix this issue:

Method 1: Checking the Server Status of Blizzard

Keep in mind that in the past, this particular issue occurred while Blizzard was in the middle of a DDoS (Distributed Denial-of-Service Attack) that rendered their entire infrastructure inaccessible. When this happened, every attempt at connecting to Battle.Net or any game developed by Blizzard returned an error.

To make sure you’re not dealing with the same kind of issue,  you should start this investigation by checking the current status of the Battle.Net infrastructure by utilizing services like DownDetector and Outage.Report.

On top of this, you can also take the time to check if the issue is restricted to Diablo III servers by conducting a quick ping test via PingTestLive.

Checking the status of Diablo 3 servers

If up have uncovered evidence pointing towards a server issue, you would also take the time to check the official Blizzard Twitter account. They typically post updates whenever there’s a major issue going on with their games.

On the other hand, if you made sure that you’re not dealing with a server issue, move down to the first potential fix below.

Method 2: Purchase the Expansion from Blizzard’s Store

If you’re encountering this problem with the Starter Edition of Diablo 3, chances are you’re seeing the error code 300016 because you don’t exactly have ownership of the content that you’re trying to access.

Once you reach the end of the Starter Edition, you will need to purchase the full game in order to continue.

As it turns out, this error is known to pop up in those instances where the game tries to connect to the Blizzard store but fails to do so, triggering this error.

If this scenario is applicable, you should be able to fix the issue by making the purchase manually from the Blizzard store (outside the scope of the game).

If you’re not exactly sure how you can do this, follow the instructions below:

  1. Exit the game and open your favorite browser. Next, access the official Blizzard shop and sign in with the same account credentials that you use to play the game.
  2. Once you have successfully signed in, click on the Games tab from the ribbon bar at the top and click on Diablo III from the list of available options.
    Accessing the listing for Diablo III
  3. From the next menu, click on Diablo III (under games) or pick a different game version if you want all to get the expansions.
  4. Once you complete the purchase, follow the on-screen instructions to enforce the purchase on the local installation of Diablo III.

If you already had ownership of the game and this method was not necessary, move down to the next potential fix below.

Method 3: Update Blizzard Account Password

As it turns out, you can also expect to see this error because of a weird overside on Blizzard’s part where the game client doesn’t support passwords bigger than 16 characters – Blizzard’s Account page allows you to create a password of over 16 characters, but you’ll be unable to use it to login inside Diablo III.

A lot of affected users facing the 300016 error code due to this problem have reported that the issue was finally resolved after they’ve used the Blizzard Account web page to change their password to a string of 16 characters or under.

If this oversight gets fixed in the issue remains to be seen, but meanwhile, you can avoid this error entirely by changing the password following the instructions below:

  1. Access the official web page and sign in with your user credentials by clicking on My Account > Login – Make sure you use the same account as the one you use when playing Diablo III.
    Login in to your Diablo III account
  2. Once you have successfully signed in to your account, click on your account menu, then click on Account Settings from the context menu that just appeared.
    Accessing the Account Settings of Blizzard
  3. Once you’re inside the Account Settings menu, click on Security from the menu on the right, then click on the Update button from the right-hand side.
    Accessing the Security tab of Blizzard
  4. At the next tab, enter your old password, then the new one, but make sure to use a password equal to or less than 16 characters in order to avoid issues with the Diablo 3 client.
  5. Once you successfully manage to change the password of your Blizzard account, access Diablo 3 again and see if you’re able to sign in without encountering the same kind of error.
    Changing the password Diablo 3

If the issue is still not fixed, move down to the next potential fix below.

Method 4: Updating the GPU Drivers

If none of the methods below have worked for you, you should also take the time to check whether you’re not actually dealing with a severely outdated instance of the GPU driver.

Several affected users that were dealing with the same issue have confirmed that they were finally able to play the game without encountering the same 300016 error after updating their GPU drivers as well as the physics module requirements.

If this scenario is applicable and you suspect you might be dealing with an outdated driver, follow the instructions below to update the current GPU driver and ensure that Diablo III has all the graphical software requirements in order to run on your computer:

  1. Press Windows key + R to open up a Run dialog box. Next, type ‘devmgmt.msc’ and press Enter to open up Device Manager. If you’re prompted by the UAC (User Account Control), click Yes to grant admin access.
    Opening Device Manager via Run command
  2. Once you’re inside Device Manager, scroll down through the list of installed devices, then go ahead and expand the drop-down menu that’s specific to Display Adapters.
  3. After you manage to expand the correct menu, right-click on the GPU driver that you want to update, then click on Update driver from the context menu that just appeared.
    Updating graphical drivers

    Note: If you’re seeing this issue on a laptop with both a dedicated and an integrated GPU, you will only need to update the dedicated component since that’s the one that will be used during the rendering of Diablo 3.

  4. At the next screen, click on Search Automatically for updated driver software. Next, wait for the initial scan to complete, then go ahead and follow the on-screen instructions to complete the installation of the new driver version in case a new one is identified.
    Search Automatically for updated driver software
  5. If a new driver version is found and installed, reboot your computer and launch Diablo III once the next startup is complete to see if the issue is now fixed.Note: In case Device Manager will not find a new driver version to replace the current equivalent, you should use the proprietary software released by your graphics card manufacturer to scan your system and see whether there is a new version that you can install. Here’s a list of tools that you can use:GeForce Experience – Nvidia
    Adrenalin – AMD
    Intel Driver – Intel

If this investigation has revealed that you were already using the latest version of the GPU driver, move down to the next potential fix below.

Method 5: Updating Game using via VPN connection (if applicable)

If you are only encountering this issue while attempting to play or update your Diablo III installation from work, school, or a public network, chances are some kind of network restriction is preventing your computer from communicating with the Diablo server.

It’s not uncommon for network administrators to impose restrictions of this kind in order to prevent the network users from hogging too much bandwidth. Another scenario that might cause the 300016 error with Diablo III is an ISP that is actively using Level 3 noded.

If this scenario is applicable, you should be able to bypass this error entirely by using a VPN client that will allow you to make it seem like you’re bypassing the network entirely when exchanging data with the Blizzard server.

Important: There are some drawbacks to this error. Funneling your data exchanges through a VPN will mean that your ping will get worse, which will end up hindering the experience if you’re playing online.

If you’re comfortable with this, we’ve made a list of VPN tools that you can safely use for gaming.

In case you are still seeing the same error code even when utilizing a VPN, move down to the next method below.

Method 6: Release DNS and Flush your IP Configuration

If none of the methods above have worked for you, you should start investigating a potential network inconsistency that might be causing the 300016 error to appear when you attempt to connect to Diablo III servers.

Some users that were also dealing with this issue have confirmed that the issue was finally fixed after they did a complete Winsock reset procedure from an elevated Command Prompt and then successfully flushed all relevant DNS information.

If you haven’t tried this yet, follow the instructions below for step-by-step instructions that will walk you through the entire process:

  1. Press Windows key + R to open up a Run dialog box. Next, type ‘cmd’ and press Ctrl + Shift + Enter to open up an elevated Command Prompt. When you’re prompted by the UAC (User Account Control) prompt, click Yes to grant admin access.
    Accessing an elevated CMD prompt
  2. Once you’re finally inside the elevated CMD prompt, type the following commands in the same order and press Enter after each one to renew the IP configuration and effectively reset every TCP and IP data that might be responsible for the apparition of this issue:
    ipconfig /release
    ipconfig /renew
    ipconfig /flushdns
    nbtstat -R
    nbtstat -RR
    netsh int reset all
    netsh int ip reset
    netsh winsock reset
  3. Once you manage to process every command above successfully, go ahead and close the elevated Command Prompt and reboot your computer.
  4. After your computer boots back up, launch Diablo III once again, connect to the servers and see if the error is now fixed.

Kevin Arrows

Kevin Arrows is a highly experienced and knowledgeable technology specialist with over a decade of industry experience. He holds a Microsoft Certified Technology Specialist (MCTS) certification and has a deep passion for staying up-to-date on the latest tech developments. Kevin has written extensively on a wide range of tech-related topics, showcasing his expertise and knowledge in areas such as software development, cybersecurity, and cloud computing. His contributions to the tech field have been widely recognized and respected by his peers, and he is highly regarded for his ability to explain complex technical concepts in a clear and concise manner.