I am unable to upload to some, but not all of my Arduinos. I have already done a bunch of troubleshooting and don't know what else to try next.
I CAN upload to my Uno, Leonardo, and 3 Megas. They all use the Arduino Serial driver, I am currently on version 1.2.2.0 dated 6/15/2015 of it. I believe this particular version came with the 1.6.5 IDE. Previously, I had a later version that came with 1.6.8.
I CANNOT upload to anything using any other serial driver, including Lilypad and Micros using an FTDI adapter, and to 4 nanos using FTDI, Prolific, and CH340 serial chips. I get the error: avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x0a
I am aware of the issues with FTDI and Prolific counterfeit clones and how the newest drivers don't work with them. I am using older drivers. I've tried numerous versions, and at the moment I am using FTDI driver ver 2.8.24.0 dated 4/10/2012 and Prolific driver ver 3.2.2.105 dated 10/27/2008. My Prolific is indeed a counterfeit clone, and 1 of my FTDIs are clones, but at least 2 of my FTDIs are genuine. I am not getting the "NON GENUINE" message.
I have performed the loopback test on all 3 of my FTDI serial adapters by connecting TX to RX. All of them loopback fine. I have performed the loopback test on the nanos by bridging TX to RX and Reset to Gnd. Again, all fine.
I can receive serial output from all of them from the existing sketches that are on them (Debug messages I put in my sketches).
I rolled back to Arduino 1.6.5 as was suggested on the forums as the last stable version for uploading. I uninstalled 1.6.8 first using Revo uninstaller to remove all traces of it.
I can successfully download and/or upload from my IR Toy, Bus Pirate, Pronto Remote, and my Christmas light controller, which use various serial chips.
I am having this problem on both my desktop computer and my laptop.
What do I do next?