Wordpress Cannot modify header information- header already sent by xxxxx

[Anay]

I suddenly started to receive following error :

Code: [Select]


Warning: Cannot modify header information - headers already sent by (output started at /home2/quiltlov/public_html/wp-content/themes/twentyten/functions.php:line 345 ) in /home/nimis/public_html/wp-includes/pluggable.php on line 689
I think I did something as was playing with template. Now I have no idea from where this error is coming because everything is working fine but only getting error in Admin --> new post. . some AJAX error is coming which is related to autosave.