Can't upload sketches to atmega328 and Arduino Uno after bootloading

I've bootloaded two chips, one on a breadboard and one on the Uno board using the pocket AVR programmer successfuly and uploaded sketches using ICSP.
Now I can't seem to do anything related to serial on either chip. I've tried different computers. For the serial on the breadboard I use the USB to Serial breakout board from sparkfun.
I've tried spamming the reset button in various patterns to no avail. On the arduino board I notice the RX light flash occasionally.
The chips are not fried as they are currently running the blink script.

The only funky thing I did while uploading was change some stuff to do with fuses that I came across on this forum as it was giving me a warning.

I only get one error and it is common for both boards/chips:

avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0xf9

etc

I’ve bootloaded two chips, one on a breadboard and one on the Uno board using the pocket AVR programmer successfuly and uploaded sketches using ICSP.

Uploading sketches using ISP will wipe out the bootloader. Reload the bootloader and then use the serial port for uploading sketches.