for over a week now,nothing shows in the frontend of my k2 blog, i have done different things like deleting and reinstalling it,but it still doesnt show in the front end, the website is www.dguruz.com/index.php/blog ,pls what could be wrong ,i have done almost everything i see on forums like enabling cache and clearing cache,it still dont work

Please enable error reporting in your Global Configuration settings, so I can see the actual error.

i have enabled error reporting,pls help me check,i culd send my login if you need it, my k2 installationson other site works except this one

I cannot see the error. Which version of Joomla! and K2 are using?

am using joomla 2.5.14 and k2 version 2.6.7

Without an actual error I am afraid I cannot help you.
You can try repairing your db and asking your hosting if
a) Has made any changes in your setup
b) Can help you locate the error_log file (usually inside your root folder) to see the actual error.

yea finally there is an error on the page :
Fatal error: Call to undefined function mb_regex_encoding() in /home/dguruzco/public_html/components/com_k2/helpers/route.php on line 68

what should i do

It seems to be missing the multibytes funtion. You have to inform your hosting provider and show him this error.