Wemos D1 R2 not detected from Laptop

Board version: Wemos D1 R2 (V2.1.0) Based on ESP8266

Hello Blynk community,

My Laptop does not detect my ESP anymore. I do not even find an option in the device manager. It is like my Laptop completely ignores the ESP. I tried serveral USB cabels and all different USB ports, but nothing helped.

I am sure that my ESP works because the Blynk App shows action. Also the light of the chip turns on everytime I connect it to the laptop. Furthermore I tried different chips which I know that they are working.

I’ve never had problems like this before. My laptop always detected the ESP8266s (serveral ones) very fast. It is like it came from out of nowhere.
A few days ago I cleaned up my Laptop to reduce working memory. Maybe I deleted something which had to do with the USB drivers for the ESP?

Therefore I downloaded and installed CP210x usb to uart bridge vcp drivers for windows 10, but that also didn’t work. Are this even the right drivers for my Wemos D1 R2?

I am not sure what to do anymore. Could you help me with this?

Best regards,

Open device manager in windows and watch the COM PORT section while plugging in your device. Does anything appear?

You need a CH340 driver…


My device manager doesn’t even show “com port” or “other devices”. As I said, it doesn’t even recognize that something is connected.

I installed CH340G driver but it’s still not working. Nothing changed.

When I try to install the driver this message shows up:

Then I check the device manager, but there is still nothing.

Best regards,

You should probably try either a different computer or a different board - or both - to narrow-down the source of the issue.


Ok. I’ll try a different computer.
Thanks a lot !


Does your laptop recognise other USB devices? (thumbdrive, printer etc?)

Seems like you removed something when you . . .


Yes it does. There are no problems with my smartphone for example.

Anyway, i tried a different laptop and now it works. Maybe I need to check settings from my old one.

Thanks a lot!


This has happened to me on a Toshie C50 - installed Arduino IDE, installed CH340 driver, able to program the Wemos D1 R2 and D1 Mini, thought “great” powered off, next day - nope no port created for either, board not found. Uninstalling the driver and reinstalling did nothing, so I started to use an ancient PC with Win7 or 8, which finally died. Meanwhile I’d flattened and rebuilt the laptop so installed new copies of Arduino and Ch340 again, again it all worked - once - and then no more. But still detects UNO and Mega boards. Definitely not my favourite issue at the moment because I have no other machine to put into service. If anyone’s heard of a solution to his I’m more than open to it. Cheers!

Lots of suggestions about what to try here:


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TY good informative thread but didn’t (exactly) solve my problem - but in a way it did. I tried a different cable, (no luck) and set Arduino up to be a Mini Pro, (no luck) and went back to the original cable and - turns out I have three dodgy USB ports on my ancient and much-used laptop. Tried every cable I had in every port, and just by jiggling it, suddenly a COM3 appeared in Arduino. Mega2560 and its cables didn’t care, it’s bulletproof, Nano and Uno cables ditto, so I’m guessing the serial uart of the D1 is particularly prone to contact noise or impedance. I literally had three or four of every cable bought at fleamarkets and supermarkets and reputable suppliers, they work for everything except the D1R2. Even the D1 Mini and some TTGO gear is fine on all those microUSB cables. Lesson: Murphy is a rotten scoundrel.

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It’s late, and I’m - annoyed, - and tomorrow I’ll clean the port contacts with IPA and a thin swab. I reckon this might even fix the issue. Spitballing ideas with my better half and we decided that maybe just maybe some chip manufacturer produced a slightly out of spec chip that got distributed among various companies building different boards because it was cheap and so now some D1 Minis, some D1R2’s, and maybe some others, have just a little bit more trouble with contact noise. Anyhoo - I’m outta here. Thank you again for the link.

Probably more likely to be the voltage regulator on these boards, or the laptop not supplying 5v from the USB port (or that 5v not making it to the Wemos via a high resistance connection).

Also, some USB cables only have two wires in them (power and GND) so can’t be used for data transfer.

I have a USB tester which shows the voltage and current being drawn by the device, and this can be extremely useful when trying to diagnose issues.


I connected a D1R2 project to the worst USB port and uploaded a short code that ran the attached relays etc and sent status messages back to the terminal window - they kept right on working when I wiggled the USB connector but I get the feeling the odd status message may have gone missing. And no - thanks to a well-timed visit from some tradespeople where I had to spend some time, I still haven’t cleaned any of the ports.

It could of course still be voltage sag affecting borderline voltage-sensitive comm circuits though. I might invest in a USB analyser myself, they’re quite cheap these days.

Lastly, I know this particular Toshie has always had issues with USB, and it could be a fault with this laptop. Also have a vague memory that a friend with another Satellite had some kind of USB issues too. And once again it’s early morning so I’ll hopefully be able to do a few more test tomorrow, emergencies permitting. %)

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