1. Login to plesk
   
   
2. Select the file/folder that is facing permission issue.
   
   
3. Click on the change permissions option as given in screenshot below
   
   
   
   
4. Select the option "Allow inheritable permissions from the parent to propagate to this object and all child objects. These include these with the entries explicitly defined here" as given in screenshot below
   
   
   
   Please ensure that Application pool group is given WRITE permission to required files/folders.
   
   
5. Click Apply.