When you launch your PTS client you will be asked to enter an account name. This account will remain 'unregistered' until you fund the account and then optionally register the account. Once you register the account name, you can use the account name to receive funds. Until then, if you want to send money to an 'unregistered' account, you need to do the following:
1) Click 'My Accounts' in the left menu bar
2) Click the name of an existing account on this page (or click "Create New Account" to create a new one)
3) On the next page, under your account name, you will see an 'Account Key' which is a long hash address starting with the letters 'PTS...'. This is your account's public key. You can fund your account by sending PTS to this account key.
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