Error database import

I was forced to remove the whmcs database and reinstall whmcs. Now I was told I can place back the database. I follow instructions but when I import the database as a zip it says no tables added and if I try to import it as the file inside the zip it says

Fout

SQL-query:

CREATE TABLE `mod_onlinenic` (
`id` int( 10 ) NOT NULL AUTO_INCREMENT ,
`domain` varchar( 255 ) NOT NULL ,
`lockstatus` tinyint( 1 ) NOT NULL DEFAULT '0',
PRIMARY KEY ( `id` ) ,
KEY `domainid` ( `domain` )
) ENGINE = MYISAM DEFAULT CHARSET = latin1;

MySQL retourneerde: Documentatie
#1050 - Table 'mod_onlinenic' already exists

Either way i don't have my client data (the only important thing) back. Is there a way to import that part manually or the whole thing or did I just lose my data.. The only other thing I can think of is that WHMCS renamed the database name as it is generated when installing. If so, how can I fix this or find out what the old name is?

Many thanks!