Use this guide if your Display does not finish starting up, keeps rebooting, or shows code or an error message on the screen.

Most of these issues come from the DAKOS software on the SD card becoming corrupted. It is very hard to predict when this will happen, but the fix is nearly always the same: reinstall DAKOS (Fix A), and if the problem comes back, replace the SD card (Fix B).

TABLE OF CONTENTS

DAKboard Reboots After the Loading or Rainbow Screen
DAKboard Hangs on the Orange Pi Logo
DAKboard Hangs on the DAKboard Loading Page
Error Messages or Code on the Screen
Fix A - Upgrade (Reinstall) DAKOS
Fix B - Replace the SD Card
Frequently Asked Questions
Helpful Articles

DAKboard Reboots After the Loading or Rainbow Screen:

Why this happens: If your Display only reaches the DAKboard loading page or a rainbow-colored screen and then reboots over and over, it is not getting a response from your Monitor/TV over HDMI. This usually means the HDMI connection is loose or the HDMI cable is bad.

How to fix it:

Unplug the power to your DAKboard CPU.
Unplug the HDMI cable from both the CPU and the Monitor/TV, then plug it back in firmly at both ends. If you have a CPU v4, use the Primary HDMI output (the one closest to the power port) for best results.
Plug the power back in. The Display will start up.
If it still reboots, connect the CPU to a different Monitor/TV. If it reboots there too, the HDMI cable is likely bad and needs to be replaced.

DAKboard Hangs on the Orange Pi Logo:

Why this happens: This only happens on a DAKboard built on an Orange Pi 3 LTS (the CPU v3). It means DAKOS failed to load because the SD card is not fully seated, DAKOS has become corrupted, or the SD card is damaged.

How to fix it:

Remove the SD card and reseat it in the Micro SD card slot. On the Orange Pi 3 LTS, the card is fully seated when you hear a click and it does not pop back out. Reboot the CPU.
If it still fails, reinstall DAKOS: remove the SD card, connect it to a laptop or PC with a Micro SD card reader, and follow Legacy Orange Pi - Download and Install DAKOS. Put the card back in the CPU's slot, reboot, and follow the on-screen instructions or Setup - DAKboard CPU/Micro SD Card to reconnect the Display to your account.
If DAKOS will not install, or the Etcher program says it cannot write to the SD card, the card is damaged. Replace it with a 16 GB Micro SD card and repeat step 2.

DAKboard Hangs on the DAKboard Loading Page:

Why this happens: If the Display reaches the loading page and stays there (without rebooting), the browser that shows your Screen has failed to load.

How to fix it: The only fix is to reinstall DAKOS:

For the CPU v3 (Orange Pi 3 LTS), use the articles in the previous section, DAKboard Hangs on the Orange Pi Logo.
For all other DAKOS devices, use Raspberry Pi - Download and Install the DAKOS.
If you are not sure how to reach your SD card, see Upgrading your DAKOS Device. It shows where the card is on each model and how to remove it.

Error Messages or Code on the Screen:

Find the message you see in the table below. Most of them mean DAKOS or the SD card has become corrupted, often because power was interrupted while the CPU was writing to the SD card.

What you see	What it means	How to fix it
Kernel Panic, or loading, please wait….starting version 247.3-7+deb11u1 at the end of a stream of code	The base operating system that DAKOS is built on has become corrupted. This usually happens after trying to update the base Kernel, or a sudden power interruption while the CPU was writing to the SD card.	Fix A
busybox v1.35	Similar to a Kernel Panic. The system could not load its main files during startup and dropped into a recovery shell (initramfs). This is most often caused by an interrupted write to the SD card, like a power outage or manual reboot.	Fix A
A command prompt such as dakboard@dakboard-(DAKOS Serial):~$	The base Kernel loads, but cannot reach the DAKboard user account's loading scripts. This can happen if the code was edited, the browser fails to start, or the DAKboard user was deleted.	Fix A
Can't Open Display	The same causes as the command prompt above, showing a different result.	Fix A
A pop-up saying Free up space to continue or Some features on chrome-extension://	Your Screen used too much browser cache or memory while loading, or there was an error moving data to the SD card. The extension mentioned is usually the one that provides the touchscreen Back button.	1. Reboot by unplugging the power and plugging it back in. 2. If it comes back, Fix A. 3. If it still comes back, Fix B.
Panic not syncing: VFS unable to mount root FS on unknown-block	DAKOS cannot read its main system files during startup. You will get this error if you are trying to start DAKOS from a USB Micro SD card reader (DAKOS cannot be read from a card reader at all), if DAKOS is corrupted, or if the SD card is bad.	1. Make sure the SD card is in the CPU's built-in Micro SD card slot, not a USB card reader. 2. Fix A, or Fix B and then Fix A. Either way, the card must go back into the built-in slot.
Low Voltage Warning	A false alarm. Older versions of DAKOS misread the voltage being supplied and showed this warning even when the power was fine.	Fix A. Upgrading DAKOS removes the false warning.
failed to open device: sd card cmd81a0010	The CPU could not communicate with the SD card during startup. Seen mostly on Raspberry Pi 4 and 5. Usually caused by a poor power supply, a faulty SD card, or a loose connection.	1. Use the supplied power supply: the Raspberry Pi power supply for the CPU v4 or v5, or the 12-volt supply that came with the Touch 22 Wall Display. 2. Make sure the SD card is fully inserted (see Upgrading your DAKOS Device for where it is). 3. Fix B.
blk_update_request: I/O error or i/o error buffer error initramfs	The base Linux kernel cannot read the SD card. This can be caused by a problem with the card or its connection, bad sectors on the card, or corrupted files.	1. Fix A. 2. If it comes back, Fix B.
Login time out after 60 seconds	Not a time-out. The DAKboard user account in DAKOS has been corrupted, most likely during a read or write on the SD card.	1. Fix A. 2. If it comes back, Fix B.

Fix A - Upgrade (Reinstall) DAKOS:

Reinstalling DAKOS replaces everything on the SD card with a fresh copy of the latest version. It also clears your Display's link to your account, so you will link it again afterward.

Follow Upgrading your DAKOS Device. It shows where the SD card is on each model, how to remove it, and which install article to use for your CPU.
Install the latest DAKOS using Raspberry Pi - Download and Install the DAKOS, or Legacy Orange Pi - Download and Install DAKOS for the CPU v3 (Orange Pi 3 LTS).
Put the SD card back into the CPU's built-in Micro SD card slot and plug in the power.
Follow the on-screen instructions or Setup - DAKboard CPU/Micro SD Card to reconnect the Display to your account.

Fix B - Replace the SD Card:

Though rare, an SD card can physically fail. If reinstalling DAKOS does not work, the problem keeps coming back, or the install program cannot write to the card, replace it.

Get a new 8 GB or 16 GB Micro SD card. These sizes have proven the most reliable with DAKOS. You can also buy a replacement card with the latest DAKOS already installed from our Shop.
Unless you bought a card with DAKOS already on it, install DAKOS on the new card using Fix A.
Insert the card into the CPU's built-in Micro SD card slot and reconnect the Display to your account.

Frequently Asked Questions:

Will upgrading DAKOS help?

Yes. Keeping DAKOS upgraded improves network stability and performance, and lets you take advantage of updates we make to our services. It is especially helpful for an older or second-hand Display that is still registered to an old account or cannot connect because of security updates, as upgrading removes the old serial number and lets you set the Display up as a new device. See Upgrading your DAKOS Device.

How often should I upgrade DAKOS?

DAKboard patches bugs and releases updates to our services every week, but DAKOS upgrades happen less often. We only rush a DAKOS upgrade when we find a bug or need to add improvements. Changes to our services may cause features to stop working on older versions, so if something is not working properly or seems to have changed, upgrading DAKOS will most likely fix it.

If DAKOS keeps getting corrupted, does this mean my CPU is bad?

Not necessarily. The CPU itself cannot damage DAKOS. Corruption only happens when reading from or writing to the SD card is interrupted, most commonly by a power interruption. Failing power supplies, bad data coming back over HDMI, input from connected devices, or interruptions while loading a Screen can also trigger it. The only part that can fail and cause corruption directly is the SD card. If corruption keeps happening, replace the SD card (Fix B).

Still stuck? See Report a Bug, Request a Feature, or View DAKOS Release Notes to report the issue to our team.