I am getting this error in my header:

HTML Code:
Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /home/content/b/e/g/beggarsbones/html/store/includes/classes/class.smtp.php:2115) in /home/content/b/e/g/beggarsbones/html/store/includes/functions/sessions.php on line 215

Warning: Cannot modify header information - headers already sent by (output started at /home/content/b/e/g/beggarsbones/html/store/includes/classes/class.smtp.php:2115) in /home/content/b/e/g/beggarsbones/html/store/includes/init_includes/init_templates.php on line 155
a timeline: last full backup 9/30. 10/1 or 10/2 i installed a mod or two that didnt really work, and so i decided to go and replace the files (includes) and set it to do so when i was leaving for work. i forgot that the program gets hung up on configure.php and cancels the download halfway though. i get to work and check on the site and get these errors. i dont have access to the 9/30 backup, but have a clean version of 1.3.7 and replaced some of the error files to get it to work. (was also getting these errors at admin, i couldnt log in)

i come home today, and begin to resume the 9/30 backup. do it all, and the error is still there. same with my 9/19 backup. i dont understand what it is getting hung up on, i've replaced files like this many times.