blank page after moving the site

Good morning,
I've a problem with my site. I moved it on a new server and then it didn't work fine because I had a blank page as homepage. After a few attempts, I tried to unistall SefAdvance and now my site work fine again. I tried to install SefAdvance again and I get a blank page problem back. I get the blank page even when a try to open sefadvance control panel. Why? what can I do?
Thanks

Blank page is an error page. See www.sakic.net/support/faq/general/#3

Hi Saka, thanks for reply.
I enabled "error reporting" in Joomla configuration, now I can see this error message in my homepage when I install sefadvance :

Deprecated: Function eregi() is deprecated in /home/mhd-01/www.cellularihitech.it/htdocs/plugins/system/sef_advance.php on line 24

That's not an error, it's a deprecated message. It should work fine regardless of that. Any other errors?
Which version of Joomla is it?

I uninstalled sefadvance and my home work again, but on fronted displayed the error message : Notice: Trying to get property of non-object in /home/mhd-01/www.cellularihitech.it/htdocs/includes/router.php on line 389

and on backend this: XML Parsing Error at 1:1. Error 4: Not well-formed (invalid token)

Saka, do you have idea how I can resolve?