Folders showing lock icon

Run the following to fix your home directory permissions:

sudo chown -R $USER: $HOME

sudo chmod 777 -R /path to folder you want to delete- This would give all permissions (Read, Write, Execute) to you

The permissions (in this case 777) are as follow:

• 7 - Full (Read, Write & Execute)
• 6 - read and write
• 5 - read and execute
• 4 - read only
• 3 - write and execute
• 2 - write only
• 1 - execute only
• 0 - none

First number change Ownership of file, second affect Group of users can access, and third refers to Others user.

Owner   Group   Other
  7       7       7

after changing the permission, try and delete the folder.