SmartThings has released the instructions for resolving 33-504 error in the following thread:
I tried this method, but my router does not allow to block the UDP 123 (it’s a eero), so I need to update the firmware through the USB port. I sent an email to the support requesting the latest firmware.
Waiting for a response
Post in the thread I linked to. There is a support person helping users there 
Same issue - I have two 3v hubs that I can not add? Is there a firmware option available via the USB? I have attempted Ethernet / Wifi from my home and office to register.
I posted a link above to the thread ST created for Troubleshooting. It has instructions for resolving the 33-504 error and hub replace options if needed (first post in that thread). Post in that thread as staff are actively monitoring it.
Thank you - Made a post there
1 Like
I am having this same issue. Followed all the standard troubleshooting directions. Will you please send the instructions as well.
Read the first post in the following thread for resolving the issue. If you still encounter any problems, post in that thread as ST staff are monitoring it.
Hi everybody, Simple solution to block NTP(for routers that not permit block ports):
Find parental control on your router settings and block all NTP active servers on your country. Check https://www.ntppool.org, choose your country to see what are NTP servers for you. Block them all on parent control or create a firewall rule. If you do that you finally can add and update your hub…
Hello Itati, I am having the same issue, my hub is stuck on 33-504 error, and nothing is happening, my serial number is 5011000412. your assistance would be greatly appreciated. M/N: IM6001-V3P06
Figured it out, block UDP 123 port, update should go through, tried both android and ios.
I tried this. Blocked it on pfsense. Still don’t work
How did you tested your UDP was blocked?
Didn’t test to be honest. Was assuming one port 123 udp is blocked it would work
This is how I tested, I have tried many things, changing the subnet, different service provider, nothing helped, only blocking UDP 123 did the trick.
same issue 33-303
SN 5011100555
@Itati
Could you follow the instructions in the post below, please? Some users have had better success performing these steps at a friend’s or family member’s home, so that might be worth a try if possible
If it doesn’t work, please send me the logs by following the instructions included in the post.
This didn’t work. The error code is 33-303
Not sure if this solution is only relevant to 33-504
Could you provide the hub logs as mentioned in these steps, please?
I have attempted to follow the instructions.
First, I tried to simply press and release the reset button. This resulted in no reaction.
I then held it a while before releasing. No reaction.
I then cut power to the device, held the reset button, and returned power to the device
This resulted in the magenta light after abandoning the factory reset (then later again after completing the factory reset). After the LED changed away from magenta (in both cases), I extracted my FAT32 usb drive and inserted it into my PC
There is nothing on it.
Below are the instructions I attempted to follow
Troubleshooting
If there are any issues with this process, please leave a comment in this thread. We’ll then send you a direct message (DM) so we can collaborate with you and collect Hub logs if possible.
Capture the hub logs via a USB log dump using the steps below:
- Insert Fat32-formatted USB drive to the USB slot on the back of the hub.
- Press and release the reset hole on the back of the hub.
- Hub LED will blink magenta while copying logs.
- After the Hub LED returns to normal from magenta blinking, extract the USB drive and connect it to a PC.
- File name will be “logdump_xxxx.tgz.enc”
- Leave a comment in this thread and we’ll send you a direct message (DM).
- Then send the package via direct message (DM) to our SmartThings support team.