Hi Marcelo,
This can be easily changed by editing the appropriate Activity types to show/not show on your Calendars. Simply go to Customize > Screens > then highlight the CRM_ActivityTypeList screen name and click View to the left of it. You'll need to select the appropriate Activity types then enable/disable the Show on Calendar? option; check out the screenshot below. Remember this change will be made globally, so the changes will reflect on all of your Activity calendars.
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Hope this helps! Let me know if you need further assistance.
- Ashur
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Ashur Shamon
Lead Solutions Specialist, Professional Services
Method Integration Inc.
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