avrdude: stk500_recv(): programmer is not responding Arduino IDE is throwing this error when uploading sketches - avrdude: stk500_recv(): programmer is not responding

The problem arose just after I uploaded a blink sketch to my Arduino Mini, which worked absolutely fine. After the successful upload I tried to upload a different sketch and got the error.

I thought I had destroyed the boot loader somehow and was about to get out the Bus Pirate for ICSP but I decided to try another Arduino Mini I had lying around (albeit from another manufacturer) and got the same error.

So I'm convinced it's a driver issue as I successfully uploaded a sketch (it still runs as we speak!) then just magically without changing ANYTHING I can no longer upload.

In a futile attempt to get back to work I've done the following:
Switched the RX-TX lines (clearly not the issue as the first upload worked)
Used a different FTDI cable
used a  different programmer
(FTDI 5V/3.3V USB to TTL Basic FT232 FIO Programmer)
(USB to TTL Serial UART RS232 Adaptor (PL2303HX)
I'm fairly certain these use different drivers - FTDI and Prolific

Please help me I'm about to murder something :'(

Screencaps of error and device manager - Imgur
Is it this?

"To upload a new sketch to the Arduino Mini, you need to press the reset button on the board immediately before pressing the upload button in the Arduino environment."

https://www.arduino.cc/en/Guide/ArduinoMini