Here is the solution for How to change time zone in webmail.
Change Time Zone in Webmail:
By default, webmail selects the host server time zone. If you want to change the time zone in webmail, follow the steps in your webmail application. After changing the time zone setting, the interface displays timestamps in the new time zone the next time you log in to the web email.
HosterNe servers are located in the EST time zone.
Follow these steps to change the time zone in the Horde Webmail Application.
1: Log in to your Webmail
2: Click on the Rig icon (present as a setting), select Preferences, and then select Global Preferences.
3: Within the information label, snap-on Local, and Time.
4: Select your required time zone and click Save.
Follow these steps to change the time zone in RoundCube.
1: Log in to RoundCube and Click Setting.
2: Click Preferences and then Select User Interface
3: Select your required time zone and click Save.
Congratulation! You did it.
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