topic Re: UI8 and not working DeX in Galaxy S25

Dex issues One ui 8

Streki — Sat, 13 Dec 2025 20:48:54 GMT

Hi, my S25 ultra was update yesterday. Today I try use my docking station with USB-S and HDMI port. But not working in DEX mode. Docking only mirror my screen but DEX not starting. Why? I use 3x dos king stations from Lenovo, itec and other and now not working? Why? Samsung delete this support? Its not fun. I need working on this. Thanks for help.

One UI 8 Dex issue's

KING31DOM — Sat, 20 Sep 2025 12:06:19 GMT

Has anyone else had issues using Samsung Dex after the One UI 8 update?

Also, my screen on my phone freezes while and after I disconnect.

Re: One UI 8 Dex issue's

usermMhzV9S32v — Sat, 20 Sep 2025 12:56:52 GMT

I've been having the same issue

Re: One UI 8 Dex issue's

CEParsons — Sat, 20 Sep 2025 13:02:01 GMT

DeX working fine for me.

Have you followed the best practices after an update guide? Clearing device cache via recovery mode in particular.
https://us.community.samsung.com/t5/Tips-Tricks/Best-Practices-After-an-Update/ba-p/3200871?src=ShareByUserCM

If the issue persists, send an error report to Samsung via the support tab in this app.

Re: One UI 8 Dex issue's

afh3 — Sun, 21 Sep 2025 00:00:56 GMT

Same...

Re: One UI 8 Dex issue's

userd2YQ6sGHXI — Sun, 21 Sep 2025 19:51:56 GMT

Same problem here. S25 Ultra, 8.0 update. DEX keeps crashing. Reboot doesn't help. Clear cache doesn't help.

Re: One UI 8 Dex issue's

Eb1881 — Mon, 22 Sep 2025 06:35:41 GMT

I will like to remove the updated. I need my dex to work on my pc. The upgrade kills phone productivity. To be honest, this upgrade looks like a retrogression. Dex on pc was the most innovative app samsung had. In a competitive market with the rise of Chinese phones, I don't know whether this was a smart move.

Re: UI8 and not working DeX

CEParsons — Mon, 22 Sep 2025 10:56:09 GMT

DeX working fine for me on UI8.

Have you followed the best practices after an update guide? Clearing device cache via recovery mode in particular.
https://us.community.samsung.com/t5/Tips-Tricks/Best-Practices-After-an-Update/ba-p/3200871?src=ShareByUserCM

If the issue persists, send an error report to Samsung via the support tab in this app.

Re: UI8 and not working DeX

RineJet — Mon, 22 Sep 2025 11:17:47 GMT

Fixes to try
1. Use a Samsung DeX cable or Samsung-certified adapter (most reliable).
2. Make sure the hub supports DisplayPort Alt Mode + PD charging (plug external power if needed).
3. Manually enable DeX from Quick Settings after connecting.
4. Update phone software and hub firmware.
5. Test with different monitor/HDMI cable.

Re: UI8 and not working DeX

Streki — Mon, 22 Sep 2025 13:12:06 GMT

I tryed but devices only reset. Not recovery menu and wipe cache possible. Sometimes devices wrote to display some errors after trying to recovery menu, but restart. Nothing more...

Re: UI8 and not working DeX

Streki — Mon, 22 Sep 2025 13:16:56 GMT

UI7 working with no problem. UI8 not have Dex quick menu only Dex wireless. And menu Dex not have any chance to change. In old UI was all. Resolution, auto detection and now I have dockings to nothing.

Re: UI8 and not working DeX

AlainC — Mon, 22 Sep 2025 14:15:31 GMT

Same issue here!

Re: UI8 and not working DeX

Members_cU39ecB — Mon, 22 Sep 2025 14:18:51 GMT

No problem for me

Re: One UI 8 Dex issue's

AlainC — Mon, 22 Sep 2025 15:20:20 GMT

Same issue here!

Re: Re: One UI 8 Dex issue's

CEParsons — Mon, 22 Sep 2025 15:27:33 GMT

Downgrading is not officially available. Unofficial methods are not recommended as you run the risk of bricking your device.

Whether you read the TOS or not, you agreed to software updates when you first set up the device.

While DeX for Windows has been discontinued, both DeX and Link to Windows are still operational, retaining a large portion of the functionality.

If you dislike these changes, you can send feedback to Samsung via the Support tab in this app.

Re: UI8 and not working DeX

LongHiker — Mon, 22 Sep 2025 15:43:48 GMT

@Streki I'm not sure of you setup exactly. Just to be clear, Dex for Windows has been discontinued and is no longer supported. You shouldn't have any problem connecting to a monitor and using Dex. I have no problems connecting my S25 Ultra directly via USB C to a monitor and using Dex.

Re: UI8 and not working DeX

Streki — Mon, 22 Sep 2025 17:15:09 GMT

So after three restarts and another attempt to connect, the image and dex interface woke up. 🙂 So hopefully everything will be ok. Thank you all for the comments and help.

Re: UI8 and not working DeX

usereNvYnCHeiu — Mon, 22 Sep 2025 17:15:11 GMT

Believe this issue might specifically be for the s23 series or the s23 ultra in my case

Re: Dex issues One ui 8

userIJtIWCR10U — Fri, 26 Sep 2025 17:52:32 GMT

What fixed Dex for me was clearing One UI Home data and cache. Hope this helps someone else!

Re: Re: Dex issues One ui 8

userIJtIWCR10U — Fri, 26 Sep 2025 17:52:59 GMT

And restarting phone right after.