Warning! D:\INETPUB\VHOSTS\mydomain.com\httpdocs/wp-content is writeable!
You should change the permissions on D:\INETPUB\VHOSTS\domain.com\httpdocs/wp-content and make it more restrictive. Use your ftp client, or the following command to fix things:
chmod 755 D:\INETPUB\VHOSTS\mydomain.com\httpdocs/wp-content/ How do I go about this on Plesk?