Change the system default currency from USD to another currency. Only do this if there are no invoices or transaction data in WHMCS.
Change the default order form template. The system uses order form templates when it displays products, the shopping cart, and checkout.
Change the default product group that displays to customers. The default group displays at the top of the Admin Area list of products.
You can change the From address that your WHMCS installation uses when sending email.
The system theme controls the appearance of the Client Area and your online store.
You can check for updates to WHMCS from within the Admin Area.
Check your system cron job's status to ensure that it is running correctly. This is the first step to addressing many automation problems.