Problem with ESP8266 ESP-12E UART WIFI Shield

Hello, I'm having trouble uploading my code to the Esp8266 shield. I'm using a ftdi to do the communication with the computer and I must say that everything runs normal, IDE can identify the port and all libraries are up to date, but every time I try to upload the following error appears:

warning: espcomm_sync failed
error: espcomm_open failed
error: espcomm_upload_mem failed
error: espcomm_upload_mem failed

I'm using this article as a base:

If you could help me, I would be very grateful.

People have had mixed success with that shield.

It does seem like a good write up and is not too old.
Mine was a little more responsive after I updated the quite old firmware on it.
Chinese suppliers don't tend to update software or firmware much.

However I abandoned mine in favour of other ESP's after a long struggle.
But the approach he uses is not one I have tried.
I know the shield can be used in standalone mode quite easily.

May have to blow the dust off this one and give that a shot.

Thanks for replying, could you explain what approach you used earlier with this shield? Or do you think you should upgrade the firmware?

It took me a while to get the firmware updated as there were a few choices.
Pretty sure I ended up getting one that had better math functions or some such.
Almost sure I also got it by digging around the Espressif site a lot too.

Also tried a few different flashing methods specific to the ESP chips and did it with a USB/serial adaptor in the end. Again after a few failed attempts.

All this was so long ago.
I do wish I could be more specific but I was just trying things almost at random while tearing my hair out.

I do know there is an easier way by setting the switches on the shield to the correct position and using the Arduino as the USB connection to flash it.

Almost certain I used FLASH TOOL 2.4 (probably updated by now)
The "espcomm" errors are nearly always to do with a COM port setting (lots of experience of those LOL)

ESP's can have two baud rates including an odd one used at boot and another at runtime.
Thats why sometimes you might see garbage on screen before you see real messages in a serial terminal.

Make sure that whichever firmware you get DOES MATCH ! (made that mistake a few times too but easy to rectify with the flasher)

Once I had the newer firmware in, it was almost usable but just didnt quite do what I wanted and even the developers admitted it wasnt 100%.
Some people may have had lesser projects and maybe thats why they got it to work better than me.

EDIT:
This is the initial guide I used

It is for the 01 series but the same principles apply just the packages are different.
Also see they updated the flasher to 3.6.5 and it looks much better.

Thanks for the great help, I will read the article and as soon as I have vacations I will try to implement this. Sorry for the delay.