Solution to Disk Read/Write errors when updating game client

[CokeSpray 7,274]

 Ever since update 1.49 (1.70.1945) (or around that update) there was a weird and annoying error which prevented many people,including myself, to update the game client properly. The error pops up randomly during major client updates,reporting an error while reading/writing files on your disk. It would then ask you whether you would like to retry the download,only to reappear again after the launcher has analyzed the game's files and prepared everything for downloading.
 
The annoying part of this error was that in the long run,it would prolong your update time for more hours then really necessary and would have you sit next to your PC for hours,monitoring and restarting the download process over and over. It's bottom line frustrating,as I'm sure most people who experienced this issue will agree with me.
 
This is how the error looks like during client update:
[spoiler]

Note: This screenshot is from an older version of the game. The latest error report also includes a more detailed report on which file(s) it can't read/write.
[/spoiler]
 
Thanks to the help of Ouiche and FredericusRer, I will explain below how to get rid of this annoying error,so you can download future updates with ease.
 
Important: This guide is only valid for Windows OS and may not work for other OS's (Mac,Linux,iOS..)
 
The error is being caused by your anti virus software interfering with the WT game directory folder that the launcher wishes to edit. It appears that this issue only affects users which use Avast! or Avira anti virus softwares.
 
There are two methods to fix this issue,both similar to each other. The first method is more of a "temporary" fix,easy to do,only takes a couple clicks. The second method is a long term solution which takes a couple more clicks then compared to the first method,but will fix the error for good and doesn't present to be much of a difficulty either. Both methods require you to perform actions through your antivirus software.
 
Method #1 - Easy,temporary fix - Turn off anti virus software during update*
This is the fast and easy fix,however this process will have to be repeated every time a new large update comes out.
 
Step 1. -  Before opening the game launcher,you will need to turn off your antivirus. Example with Avast! - right click on the avast icon on your toolbar and select "Avast shields control" and select for how long you want to have it off (preferably for as long as you need to update the game).

 

*Do this at your own discretion and risk,as it may leave your PC exposed to threats.
[spoiler]
          
          [/spoiler]
         
2. Now open the launcher and update your game.
 
Method #2 - Making exception in antivirus software for the WT Game directory
This method takes slightly longer (not much) then the first method,but once you have done it,the Disk R/W errors should be history! 
 
Step 1. - Open your antivirus software (in my case,Avast!)
Step 2. - Go to the settings/options where you can set exceptions/exclusions. For Avast!,you go to Settings > General > Exclusions.
[spoiler]

[/spoiler]
 
Step 3. - You need to add the War Thunder game directory as an exclusion in the "Exclusions" section. You do that by selecting the "File paths" tab,then click on "Browse",find the WT folder on your HDD/SSD and select "Add" in the bottom. 
Hint: make sure to tick the box in front of the WT folder once you find it before you press "Ok".
 
Step 4. Press Ok and close the anti virus. You may now run the WT launcher and update the game.
 
 
I hope this thread will help anyone who has the same issue as I had.