When I imported my contacts from Windows Live Mail, they were all imported into emclient contacts folder, but there a % symbol after the last name and after the first name of the contact.
Any way I can get rid of this %?

As far as I know, you can’t do it directly in eM Client, but maybe someone else has managed it.

However, you can do it by exporting your contacts to a vcf file and then using an editor to search and replace the %. This character does not normally appear in a vcf file created by eM Client, so it is fine to delete them all without compromising the data. Then after saving the edited file, you can import it back into eM Client. You want to use a separate folder, or delete the corrupted contacts before you import.

Before doing anything drastic, you should always make a backup using Menu > File > Backup.