Arduino R3 Uploading issues

So I have had this Arduino R3 for a while now and it worked fine for a long time....uploaded many sketches and all worked, even removed chip and replaced for more permanent projects and always worked...

I took a break from fiddling and recently tried to upload a project simple blink sketch but its not working..
The 328p-pu chip is fine as I have programmed it on breadboard using my little thumb usb programmer and have even used atmega 2600 board with success so im thinking there is a small fault with my uploading part of this board...

My question is...IS there a way to diagnose which part is faulty? if I program a chip and stick it in to the board it works fine but still no uploading...the leds do not flash or anything during upload process and all I get is a get sync error .all settings are correct and drivers are also right as I said It used to work.

Tried the loopback test?

thanks for speedy reply, no I had not even heard of it but SEARCHED test and tried it..

Everything returned as typed. so that all works fine.

Removed power, disconnected jumpers. and retried to upload blink sketch and it gets about 90% and tx led blinks once and then hangs saying get sync error etc

sorry I meant the RX blinks and I did it a few times. once it blinked once and another time it blinked 3 times before saying get sync error

Had another go at this this evening but still same issues.
Any help appreciated.....................................

:0 :blush: I figured it out.............For some reason and its really stupid but a true novice mistake that took me all this time to figure out.....

IF YOU ARE GOING TO PUT PIN ID LABLES ON YOUR ATMEGA CHIP FOR EASE OF REFERENCE MAKE SURE YOU PUT THEM THE RIGHT WAY AROUND!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

looked at a picture of uno r3 on google and saw the notch in chip the opposite end of board to way mine was... what I thought was pin 1 was not pin 1 LOL

SO IT NOW WORKS ONCE MORE YAY FOR ME SORTA!!!

Case Closed!!!!.

But your experiment means that the chip survived the "wrong" connections...