pacosxm on "[Plugin: Wordfence Security] Correct permissions when Wordpress install is in a sub-folder ?"

Hi,
Wordfence work well in all my Website exempt two which are install in a subfolder :

http://www.mywebsite.com/wp/ actually my "wp" folder is 755 but I got this Wordfence message :
Scan terminated with error: Wordfence could not read the contents of your base WordPress directory. This usually indicates your permissions are so strict that your web server can't read your WordPress directory.

So, what are the correct permissions to fix this issue.

Thanks

https://wordpress.org/plugins/wordfence/