Hello, sorry for the delay.
Intro Rant Gist:
I recently purchase an aftermarket UNO to see if i had similar issues just for fun. Based of what I had read I was concerned when I plugged in the board and had the same sync error originally encountered. In short, the same sync error will occur in one week old, 2 year old and aftermarket UNO from some suppliers( No guarantee, missing bootlog would void such a statement) .
The error code titled in this intro is something i can frequently run into and follow a simple step process.
The error code “not in sync” arises for me detailed earlier.
Going into the path to adjust the com# described earlier and adjusting the number, resetting the computer each time till the board uploads.
As described the vague path is:
Systems–>Device Manager–> Port selected after updating driver–>properties–>port settings–>advanced settings–> Com #
The com# as shown in the attached print screen shows what com#'s are in use.
First update the software/ driver for the board i you haven’t already described earlier.
With the board plugged in restart the computer.
Open the Arduino software (IDE) Select the appropriate board type and Visible com port.
Attempt to upload the sketch (if the sync error remains continue)
Select a different com# not in use in the advanced settings.
with the board plugged in restart the computer.
Repeat opening the IDE and selecting the board and com then upload the sketch.
If you have multiple devices visible on your IDE and Windows port its important to unplug and replug in the board to identify what ports are constantly in use to not get confused.
Restarting between changes is also important.
Additionally, when viewing the board and port # be sure to look for a updated name next to the selected port#.
If your board like mine is a Uno windows may select the name (Arduino Uno) or the name can be changed in the device manager advanced settings of windows if you like. I showed this earlier in an image.
If this is not next to the port you selected, you may have to restart the computer, and if it still dosent work cycle through to a different port #.
In my case I have three boards so the com # for one is different for another so although it shows up in the IDE it wont update the board until i cycle through to the correct com #.
Confusing I know.
But this gist as i sip down some Glenlivet is to restart the computer after connecting a board. the restart each time you need to change the com#. and try to select the lowest com#'s first.
This is advice from a very green novice so please take these words as theoretical and not fact. (large grains of salt)
Ask questions if you have then and ill check in every so often as i encounter new issues I attempt to resolve myself.