This is one of those advise that I hope that you do not have to take advantage of. Hilton HHonors accounts become inactivate and all the points forfeited IF you don’t have a stay at Hilton hotel OR any other partner point activity in any 12 month period.
Although the points have been forfeited and the account deactivated, you can restore it by contacting Hilton HHonors by phone or email. It helps if you happen to have your account number on hand. The customer service can reactivate it and email you a new PIN number to regain the online access. Sometime they might give you a small bonus for your next stay as happened in the case above. (Thanks for LoyaltyLobby reader forwarding it to me)
Conclusion
Just make sure that you have any point earning activity within 12 month period for your Hilton HHonors account not to fall inactive status. If that happens, just contact the customer service by phone or by email and request them to reactivate your account.