To access your voicemail recordings go to Services -> Voicemail
From here you will want to click on Greetings for the voicemail box that you wish to upload the greeting to
Once in the greetings page you can choose to upload a greeting from a file on your computer. You can do this from the top right where you see 'Select a file' and then click Upload
Once uploaded you will see the greeting in the main window. If you have multiple greetings you can listen to them from the portal and choose which one you wish to use.
You can upload up to 8 recordings per voicemail box.
NOTE: When uploading a Voicemail recording make sure to upload a wav file.