You can follow malr link above to install update for Windows 7 (apparently helps many people).
It is for Windows 7 64-bit.
For Windows 7 32-bit I found this link in Google (hopefully it works too, I couldn’t check, i’m on 64-bit).
https://www.microsoft.com/en-us/download/details.aspx?id=45588
If you are afraid to install the update, just saying that it is possible to delete update later. Or just use link to older folder version below.
If you want “Battle.net.13401” (working folder), somebody on EU forum provided a link:
https://www.mediafire.com/file/2op97srx95eut4a/Battle.net.13401.zip/file
(source post where I got the link from, you can skip that)
Ошибка запуска Battle.net - Поддержка - Blizzard Forums
“Battle.net.13365” - As an alternative I decided to provide a link to another, earlier folder version.
https://www.mediafire.com/file/ei5bf2dmg4k4zw4/Battle.net.13365.zip/file
IMPORTANT - Remember to delete “Battle.net.13434” (or any other similar folders Battle.net.#####).
(Why? Because Battle Net recreates “Battle.net.13434” folder EVERY TIME after successful login)