Open Thunderbird
Click Tools if you do not see if on the top menu press \"Alt\" key
Click Add-ons
Click Extentions
type in the box that says \"Seach all add-ons\" tzpush
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Press the seach button beside it
or you can download it from https://addons.mozilla.org/en-US/thunderbird/addon/tzpush/
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Click Options
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Server: https://webmail.tkhost.com/rpc.php
Check the box Use https://
Username: your email address
Password: your email password
Press Ok
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Now you can click on the tools menu
TZ-Push
tz-sync
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And it will sync.