This blog post describes what you can do if Windows doesn’t recognise the Wemos D1 Mini and there is no COM port to use it.
Before starting, lets try something simple
Your Wemos might not be found due to a faulty cable. Some cables will only transmit power and will not work.
Try using another cable, any one from an android phone should work with the Wemos. If this doesn’t work then try the next steps. Lots of viewers of this post found that simply changing the cable worked!
Why is there no COM port for my Wemos D1 Mini
The standard USB-to-serial drivers installed on Windows does not currently support the USB-to-serial chip used in the Wemos D1 Mini.
The Wemos D1 Mini won’t show in the Arduino IDE until this issue is resolved. If you are using another program to program the D1 Mini you won’t have the emulated COM port needed to program it.
However it is relatively easy to fix this by installing the correct driver for the USB-to-serial chip.
Installing the required driver
The Wemos website has the correct driver to use for the USB-to-serial chips in their Wemos range. This includes the Wemos D1 mini which I am having trouble with.
You can download the driver from their downloads website.
I downloaded the zip file
ch341ser_win.zip and ran the executable in that zip file. The zip file hashes are reproduced below:
Once the driver was installed Windows reloaded the Wemos D1 mini and correctly found the driver. The COM port then appeared in the Arduino IDE and I could successfully load programs onto it.
If you have any questions about getting the Wemos D1 Mini to work feel free to ask below.