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Den Leader (SB User ID:11869946BSA Member ID:13851045) is unable to take attendance using Scoutbook. He used it last year as a Bear Leader but he is now as a Webelos Leader he cannot. Is that feature no longer available or does he need to do something on his end? He takes attendance at Den and Pack meetings.
This Den Leader is missing the Den Admin role for his den(s). Add it, and he will be able to access the den calendar(s).
If you want him to be able to record attendance for pack events, then you will need to make sure that he is connected to all Scouts in the pack. In Scoutbook, you will also need to give him the role of Secretary or Outdoor Activities Chair.