Cisco 8841 Administration Guide

• Power over Ethernet (PoE) doesn't meet the required power-supply.
• Connected number of key expansion modules exceed maximum "Number of Units".
Solution
• Change the phone to use the same type of expansion module.
• Check the PoE the phone connected to.
• Check if the unit number is bigger than the “Number of Units".
Cisco IP Phone 8800 Series Multiplatform Phones Administration Guide
121
Hardware and Accessory Installation
Key Expansion Module Does Not Go Through the Normal Start Up Process

Cisco 8841 Specifications

General

Resolution	800 x 480 pixels
Audio	Wideband audio
Bluetooth	No
Ethernet	10/100/1000 Mbps
PoE	IEEE 802.3af compliant
Connectivity	Ethernet
Buttons	4 programmable line keys
Speakerphone	Full-duplex speakerphone
Headset Jack	Yes, RJ9
Codecs	G.711, G.722, G.729a, iLBC
Power Options	PoE
Network Interfaces	Dual Gigabit Ethernet ports
Security	Secure boot, 802.1X authentication, secure credential storage
Dimensions	40 mm
Weight	2.5 lb (1.1 kg)