No wrapup. I PING’d / tagged those members of the Brave team, because they are looking for clues, indicators re what may be going wrong. There are some possibilities in the details mentioned by kumarsuraj.
Using a computer, requires routine data backup. I run scheduled, daily backups for Internet browser data - and have been doing that for over 20-25 years. Manual backups, before that.
My preference is to create a .zip compressed file of the data, and store each file in a safe location (outside the pathways of the software), and use chronological names, example:
- 20250629_BBdatabkup.zip
- 20250630_BBdatabkup.zip
- 20250701_BBdatabkup.zip
I am usually a MacOS user, but, when using the Windows OS, I also create System Restore Points after each day of working on the computer, in addition to sometimes creating a System Restore Point before doing some things - installations, testing software, testing some issue.
Something(s) might be banged up / wounded inside a User Data folder, and the user might try to piece together a restoration - using pieces from the backup. At the following link, scroll down to “There are some key files I can share”:
‘Brave doesn't start when I run it as administrator and Brave Shield doesn't work - #73 by clifton’
My own two cents:
Windows OS > Brave Browser users > User Data tips re backup, permissions, recovering or restoring some of the data:
Windows OS users. Brave Browser data is within the folder and sub-folders of the User Data folder; location:
C:\Users\[UserName]\AppData\Local\BraveSoftware\Brave-Browser\User Data\
Also written as:
%LOCALAPPDATA%\BraveSoftware\Brave-Browser\User Data\
Let us say that you have backed up the User Data folder to a safe location - away from the BB installation paths, such as: on an external USB drive.
Next, because of some issue with BB, you decide to set aside the User Data folder - ie remove it from location:
%LOCALAPPDATA%\BraveSoftware\Brave-Browser\User Data\
for the moment, placing that User Data folder on your Windows Desktop; and then Restart the computer; and then Start up Brave Browser . . . BB will create an entirely new User Data folder that will include a fresh, new Default folder:
%LOCALAPPDATA%\BraveSoftware\Brave-Browser\User Data\Default\
Let us say, that you previously had 2 additional BB user profiles. And, you want to try and restore what you can, from them ← therefore, create 2 new additional BB user profiles ← their respective new folders (Profile 1 folder and Profile 2 folder) will be created at:
%LOCALAPPDATA%\BraveSoftware\Brave-Browser\User Data\Profile 1\
%LOCALAPPDATA%\BraveSoftware\Brave-Browser\User Data\Profile 2\
From the backup of the User Data folder that you created (and may also located on the external USB drive ← smart move!) -OR- from the User Data folder that you placed on your Windows Desktop . . . and while BB is NOT RUNNING after a Restart of the computer, there are some items that can by drag-copied (I am not a fan of Copy-and-Paste method) from the old (backed up) data location to the new.
SOMETIMES, you might succeed by “simply” replacing the new Default folder with the old ← BUT THAT MAY NOT PRODUCE THE RESULTS THAT YOU WISH.
Of BB PROFILE data, within a BB user’s profile folder, the following list of items, are known for being replaceable - BUT AGAIN, NO GUARANTEE OF SUCCESS:
BB PROFILE data, within a BB user’s profile folder (Default example):
%LOCALAPPDATA%\BraveSoftware\Brave-Browser\User Data\Default
The following list of items, are known for being replaceable - BUT AGAIN, NO GUARANTEE OF SUCCESS:
- Bookmarks [JSON file]
- History [SQLite file]
- Login Data [passwords, SQLite file]
- Preferences [majority of browser settings, JSON file]
- Sessions [folder ← do not copy]
- [but you can copy the Sessions and Tabs files:]
- Session file example: “Session_13387619522050810” [SNSS file]
- Tabs file example: “Tabs_13396004968468207” [SNSS file]
- Tops Sites [saved tiles on new tab page, SQLite file]
- Visited Links [binary file]
- Web Data [autofill data, SQLite file]
NOTICE: Re Session_13387619522050810 ← the long string of numbers are a date-and-time stamp. On a MacOS computer, the following command (date -r 13387619522050810) will reveal: Thu Apr 6 12:40:10 EST 424238744
NOTICE: A Profile 1 folder, for example, cannot be replaced by a profile folder of another name (such as Profile 2). Same for the other BB user profile folders. DO NOT CHANGE the BB user’s profile folders names.
NOTICE: The most durable files, are Bookmarks, Bookmarks.bak. They can be copied between the BB user profile folders.
SOMETIMES: A BB user has recovered passwords by using the backed up Login Data file; and sometimes by doing that PLUS using the backed up Local State file; and sometimes by a combination of: Resetting the Brave Browser Settings, using the backed up Login Data file, plus, using the backed up Local State file.
FILE AND FOLDER PERMISSIONS: See https://community.brave.app/t/browser-wont-launch-after-install/606342/18 and https://community.brave.app/t/brave-doesnt-start-when-i-run-it-as-administrator-and-brave-shield-doesnt-work/628494/41