It just looks like you haven't uploaded the language file. Make sure that the steps below were added to 'Languages/English/Admin.lng' and that you uploaded it back to its correct directory:

Code:

<edit file>
Languages/English/Admin.lng
</edit file>

<search for>
);

%smtp_txt = (
</search for>

<add before>
'advertise_set' => 'Advertisement Settings',
'advertise_set1' => 'Edit your Advertisement Settings',
</add before>

<search for>
1;
</search for>

<add before>
%advertise_txt = (
'01' => 'Advertisement',
'02' => 'This function enables Advertisement in Message Display',
'03' => 'Who can see this Advertisement?',
'04' => 'Ad Code',
'05' => 'Max number of Advertisement displayed in a Thread',
'05a' => 'Maximum value per page is',
'06' => 'Ad Title (optional)',
'07' => 'Changes have been saved',
'10' => 'Nobody',
'11' => 'Only Guests',
'12' => 'Everybody except Staff',
'13' => 'Everybody except Admins and Gmods',
'14' => 'Everybody except Admins',
'15' => 'Everybody',
);

</add before>