1. file_get_contents supports only php  versions (PHP 4 >= 4.3.0, PHP 5)
Difference in versions may cause errors.Otherwise please check the
path of the file  "blockip.txt".Some times that may wrong.

2.Second error(Cannot modify  header information  - headers already sent
by (output started  at
/home/adopt/adopthomestudyserv-www/form2mailAHS.php:50))

Are you using header  and echo in this file?Header and echo will
not work at a time.If you are not using echo in that page.Please write
'ob_start();' at the begining of the page

first warning  comes according to unavailability of blockip.txt
file. be sure to existance of file  and you may try include
("filename"); also.

send warning is about a problem in session. be sure that session
start is at top of the file content. refer
http://www.phplabsindia.com/info