The following is lengthy; please read carefully. Getting familiar with all the locations of the items mentioned, will help you a lot, before you decide to take any steps.
Please Quit all Brave Browser applications.
Where some things are at, using Mac OS X Sierra:
Root: simply a forward slash /
Root and System level folders
The “Brave Browser.app” application is located:
There, and hereafter, I am referring to the location of files and folders - assuming that a recent, stable release of Brave Browser is the only installed version. (No Beta’s. No Nightlies.)
Your machine user account folder, aka home folder “your_username_aka_shortname”:
Therein (of interest today):
System Cache files - generally you do not mess with these very often:
On the other hand, your user account “Library” folder and its “Caches” folder:
Generally, therein, you can - after quitting associated/relevant application(s), move your cache files n folders that you select
/Users/your_username_aka_shortname/Library/Caches/< files n folders >
to the Trash. For example, there are (Sierra) two Brave Browser cache directories that could be moved to the Trash, “BraveSoftware” and “com.brave.Browser” (I forgot to mention that 2nd one, “com.brave.Browser”, yesterday):
System level Application Support:
Currently (Sierra) - there is no “Brave Browser” type folder therein.
On the other hand, in your user account’s Application Support:
has a Brave Browser folder named “BraveSoftware” therein:
And therein, a sub-folder “Brave-Browser”:
And, therein, several files and folders.
Continuing with that last location and the “several files and folders” . . .
Recently (last few days of this 2nd week of August 2021) there were some temporary fixes / solutions to Brave Browser problems (for some users), where CPU/RAM usage has been high, and/or failure to successfully start Brave Browser (crashes or freezes).
Among the temporary fixes, were TWO that might apply to your situation. So, after Quitting Brave Browser:
ONE: Move to the Trash, all the contents within the “CertificateRevocation” folder (but not the folder itself):
TWO: Move to the Trash, the “cffkpbalmllkdoenhmdmpbkajipdjfam” folder:
Example screenshot of both a) the contents of folder “CertificateRevocation” and b) the “cffkpbalmllkdoenhmdmpbkajipdjfam” folder, currently:
So, when I first read YOUR original post, I wondered that maybe you need to take a swing at THOSE TWO TEMPORARY FIXES just mentioned . . . AFTER you:
First, Reminder to Quit Brave Browser (including any Beta’s or Nightlies).
Second, un-install whatever Brave Browser applications you may have installed by now.
Third, move to the Trash, the aforementioned cache collections.
Fourth, make sure that for now, you hang on to the “Brave Browser” folder that you rescued - probably you put the folder on your Mac’s Desktop (ie keep it out of the way).
Fifth, Locate the Preferences file “com.brave.Browser.plist” for Brave Browser:
And move that “com.brave.Browser.plist” file to the Trash.
THEN, after all that cleanup, install the latest stable release of Brave Browser.
IF THEN, the latest stable release of Brave Browser will NOT install, you will need Brave Support help, directly.
Because probably a required signature credential for the Installer (or some part thereof), is not correct, or some Bundle Identifier info, is not correct (something like that) - would be my guess.
(PS. Sometimes, the date info, of your computer, might be off enough, such that an installation will not proceed.)
BTW1, you have not said where you originally found the “Brave Browser” folder that you previously moved to the Trash . . . but rescued.
BTW2, I would not install a Beta nor a Nightly, unless a member of the Brave Support Team was guiding and explaining the why of it.
UPDATE: You probably found the mystery “BraveBrowser” folder, here:
If I am not mistaken, that is used when making the original, first-time installation of Brave Browser. Yet I do not know how it may be involved, subsequently.