Error codes and solutions

Our development team are constantly working to improve the user experience for everyone on Sumdog, but sometimes that can cause teething problems. Here are some error messages you may see and what they mean.


Sumdog is running slow (and you are using a tablet or smartphone)

You will need to download and use the Sumdog app, as tablets and smartphones don't have the operating power required to load Sumdog games. Our apps are optimized for use on tablets and smartphones, so you'll see a far better performance. 

You can find instructions on installing the app here.

Sumdog is running slow (and you are using a laptop or computer)

If this message appears while you're using a laptop or computer, it means your internet is running too slowly for the games to load.

There are a number of troubleshooting steps you can take to tackle slow internet speed:

  • Check your internet connection either on your computer or on the router or modem itself
  • Run an internet speed test here to confirm the download speed you’re receiving
  • Try connecting to a wired internet connection instead of wireless
  • Move your device closer to the internet router or modem
  • Turn the network connection on your device off, and then on again to see if this establishes a better connection
  • Turn the router or modem off for a minute, then switch it back on
  • Ensure there are no large downloads or demanding video streaming on the network, as this can put a strain on download speeds
  • Try having your students log on in small groups instead of all at once
  • If you are using a device with Wi-Fi, try turning that off and using the mobile 4G data network instead to see if it may be an issue with the Wi-Fi (data charges may apply)

Error code BB3742FC

Normally, this error code means that there is a network issue, or an error in connecting to the Sumdog server. Here are some things that might help:

  • If a group of students is using Sumdog together, try having them log in in batches to lessen the internet usage.
  • If you have multiple device using the same network connections, you might need to reduce the number of devices using the internet at one time.
  • Some AntiVirus programs may block Sumdog’s access to the service. Please check your antivirus program, to see if this is happening. You might need to list * as an exception on the program.
  • Try turning the internet off and then back on again.

Error code ED85E003

This error normally means that there may have been an error when logging into the account. Here are some things that might help:

  • If you are using the Sumdog app:
    • Make sure that you have updated the app to the latest version. If you are not sure, you can check the app store to see if there is an update.
    • Try closing the app and then re-opening it and logging in again.
    • If you are still seeing the error after the steps above, try deleting and reinstalling the Sumdog app
  • If you are using a computer, try closing and reopening the web browser

Error code 0B05E23A

This error can appear if the session has timed out. Try logging out of your account and logging back in again.

Error code 242D366B or A1C343C3

These errors normally appear when there has been a problem with the connection at the start of a game.
Please try these troubleshooting steps:
  • If using a computer or laptop, try closing the web browser and logging in again
  • If you are using a tablet:
    • Make sure that the app is updated to the latest version. You can check this by going into the app store and searching for Sumdog. If the app is not updated, you will see an option to 'update'. 
    • Try closing the app and reopening it
    • Try deleting and then reinstalling the app

If the error persists, please see the section below for guidance on reporting an error to our support team. 

Submitting a request to our support team

If you still see an error message after trying the troubleshooting steps on this page, or if you're seeing an error not listed on this page, please email our support team at, and include the following information:

  • What type of device were you using when the issue occurred (e.g. iPad, Chromebook, etc.?
  • What is your browser or Sumdog app version?
  • A description of the problem and the error message you saw. Please include as much detail as possible when describing the problem
  • When did the issue occur (e.g. when setting work, in the middle of a game, after pressing Start to enter a game, etc.?)
  • Do you see the error on other devices as well?

These questions will help us identify where the error is occurring so we can resolve it as soon a possible! Once you've emailed, our support team will be in touch within 24 hours (excluding weekends).