You might have come across the following error in your cPanel error log:
SoftException in Application.cpp:267: File “/home/username/public_html/foldername/index.php” is writeable by group
The issue is due to folder and files permission not properly set and cPanel not allowing them to run on the user end.
To fix this issue, simply login into the server (we need SSH access to resolve this) and run the following commands:
cd /home/username/public_html
Here, replace the username with your user.
find foldername -type d -exec chmod 755 {} \; find foldername -type f -exec chmod 644 {} \;
Replace the folder name with your project folder or if your files are in the root directory of public_html, then use the public_html folder name.
Or else
To fix it, go to cPanel File Manager, the directory where the file is, then select the file, click "Change Permissions" and uncheck the instances of "Group".