There are a number of steps to set up voicemail on the HTC One. Begin by clicking the icon to see all apps, and then touch the HTC folder where the voicemail setup controls are found.
When accessing the voicemail setup area, a welcome screen appears, and to access the controls, swipe left. At this point, the option to personalize the voicemail message appears, and the HTC handset automatically calls the voicemail number. There are a series of voice prompts that must be followed to set up the account, including setting up a passcode, a name and greeting. End the call when the prompts finish, and at this point, the voicemail is ready to use.
When the voicemail is set up, access messages by touching the Welcome to Voicemail button. Here, there are a number of options, including speakerphone, play and pause controls. There is also a slider that allows users to skip to a certain part of the message, and a trash area where deleted voicemails go. To permanently delete voicemails, access the trash can and tap the Delete Voicemails option. When a new voicemail is received, it automatically appears in the voicemail list and can be heard by clicking on the message.