WordPress MU

Hi,

I use wordpress MU but now when i try login in myblog.com/wp-admin i get this error:  and can't login to my wp-admin

I dont know what is the problem.. can you please help me?
With wp 2.6 works fine but now with wp 2.8.1 i can't login.
Anyone here can post link to download Wp MU 2.6?

Thanks

do you get any errors in your apache error logs or you php error log?

yes, i get this:

Fatal error: Call to undefined function: _x() in (...)/wp-admin/menu.php on line 35

Did you upgrade your install? Did you do it by replacing all the files or did you cut over your plugins and blogs.dir to a fresh unzip and then upload it?

line 35 of menu.php looks like:

$submenu['edit.php'][10] = array( _x('Add New', 'post'), 'edit_posts', 'post-new.php' );

I have wp mu version 2.7.1 and i install some plugins.. then i
I rent a coder and he upgrade wp mu to version 2.8.1..
After that i can't login to my wp-admin..
Error in line 35 of menu.php is about any plugin or what is it?

No its building the Posts menu but for some reason it cant find the dummy function _x.

I think you've lost a couple of files in the upgrade process. So you need to get your person back in

How can i resolve this?

Find the person who upgraded your site and get him to fix it.

Honestly that would be the best way. DId you get it fixed?

I think you can use a backup of your files and update it again.