I installed a fresh version of Backpack via php artisan backpack:install --elfinder yes
File Manager menu item to work.
File Manager menu item is not working in the menu.
I think the problem in the quotations here:

It works fine after removing the repeated quotations.
When I run php artisan backpack:version the output is:
PHP 7.4.0 (cli) (built: Nov 27 2019 10:14:18) ( ZTS Visual C++ 2017 x64 )
Copyright (c) The PHP Group
Zend Engine v3.4.0, Copyright (c) Zend Technologies
v7.0.8@d71ba61d51aec79a0a0f907991ec215dc24b09d4
@mamprogr can you confirm you are using Windows ?
Yes, I'm using Windows and Wamp
Can you test my solution in #2532 if it fixes ?
If it does fix, please leave a comment in the PR thread so when @tabacitu sees it, it knows it had been tested atleast by two persons, and would make it easy for him to merge the change.
I would like to thank you very much for submiting this issues, the upgrade to Laravel 7 should have not been so broken, a lot of stuff changed in Laravel dependencies and not all are documented, so we only know about them when we get the errors .
For that bad experience we apologize! Hope next weeks will bring better news than this! :)
Wish you the best,
Pedro
I've just merged #2532 - which hopefully fixes this. Please let us know if after a composer update you get any more issues @mamprogr . And just like @pxpm said - thanks a lot. Very helpful.
Cheers!
Most helpful comment
Can you test my solution in #2532 if it fixes ?
If it does fix, please leave a comment in the PR thread so when @tabacitu sees it, it knows it had been tested atleast by two persons, and would make it easy for him to merge the change.
I would like to thank you very much for submiting this issues, the upgrade to Laravel 7 should have not been so broken, a lot of stuff changed in Laravel dependencies and not all are documented, so we only know about them when we get the errors .
For that bad experience we apologize! Hope next weeks will bring better news than this! :)
Wish you the best,
Pedro