Installation folder won't delete

When installing joomla on an apache server I have managed to get to the delete installation folder page after tweaking the server settings, manually uploading the configuration.php and setting up the ftp layer but when clicking the delete button I just get error with no explanation of what the error is.
I deleted the installation folder manually, which seemed to work, but now trying to upload templates I keep getting can't find installation file.
I've searched for a solution but can't find one so any help would be very appreciated.