If you received this error message:

Review all error messages below to correct your data.
Apex trigger CRMGAC.TaskCounterTrigger caused an unexpected exception, contact your administrator: CRMGAC.TaskCounterTrigger: execution of AfterInsert caused by: System.DmlException: Update failed. First exception on row 0 with id 0016000000Jm41LAAR; first error: INSUFFICIENT_ACCESS_OR_READONLY, insufficient access rights on object id: []: (CRMGAC)

Upgrade to the latest version of the Activity Counter.

To upgrade, using your standard Salesforce credentials, login to appexchange.com > Go to "My Accounts" > Activity Counter > Click on the "Upgrade Available" button.