193859 OScommerce PHP repair

My Os commerce site is not sending emails it returns the following error message when trying to send an email from the admin section Warning: fsockopen() [[login to view URL]]: unable to connect to mail.(sitename).[login to view URL] in /public_html/admin/includes/classes/[login to view URL] on line 105 Warning: Cannot modify header information - headers already sent by (output started at public_html/admin/includes/classes/[login to view URL]) in /home/tensecon/public_html/admin/includes/functions/[login to view URL] on line 18 My Host seems to think this contibuti9n needs to be installed [login to view URL],901 I'm not sure...i just need it done quickly by someone well versed in oscommerce