Only remove your custom Zimlets. You should not remove Zimlets that are shipped with Zimbra Collaboration Server. If you do not want to use the Zimlets, you can disable access.
In the Navigation pane's Configuration section, click Zimlets. The Zimlets content pane opens.
Select the Zimlet and click Undeploy. An Information box asks you to verify that you want to remove the Zimlet.
Click Yes. The Zimlet and all associated files are uninstalled. The Zimlet zip file is not deleted. You can remove the Zimlet from /opt/ zimbra/zimlets.