Lenovo C400 manual Item, Solution, Hardware→ Device Management is enabled. Then

Item	Solution
Finding a projector’s ID and Session	When the wireless projector is idle, its ID is
Key	shown at the bottom left corner of the projection
	screen. For a WEP-enabled projector, the Session
	Key will also be shown.
Wireless projecting software not	Make sure that the current user has
launching correctly	Administrator’s privileges, and that Lenovo
	WDLP Driver item in My Computer → Property→
	Hardware→ Device Management is enabled. Then
	re-install the program.
If the prompt No WLAN adapter	Confirm that the WLAN adapter is in the laptop
appears in the projector list window	and its drivers are installed. Make sure that
	WLAN adapter item in My Computer →
	Property→ Hardware→ Device Management
	Wireless adapter is enabled.
If the ID of a projector does not appear	Make sure that the antenna of the laptop’s WLAN
after refreshing several times	adapter is turned on and try again. Remove and
	then re-insert the WLAN adapter, repair or
	disable it, then re-enable. Select Information→
	Wireless Setting→ Wireless Repair in the OSD
	menu. Try to refresh again after the ID of the
	projector appears on the bottom left corner of the
	projection screen.
If wireless projecting fails	Firewall software can interfere with the
	performance of the wireless projector. Try
	disabling any firewall software. Make sure that
	there is no network routing software which may
	change the network configuration and try again.
	Repair the WLAN adapter by re-inserting, or
	enable/disable it and try again.
Projected image takes more than 30	Strong radio interference can interrupt the
seconds to refresh	operation of the projector. Typically it will recover
	within 30-60 seconds.
Cannot connect to the Internet while	Wireless projection uses a wireless adapter card
projecting wirelessly	(WLAN) in your laptop computer. Therefore, you
	cannot connect to the Internet unless you have a
	second wireless adapter, or you have a wired
	connection.
During a wireless projection session the	Due to the possibility of unreliable networks, the
WLAN adapter is unplugged or	projector takes some time to realize that the
disabled, but the projector screen	WLAN adapter in the laptop has been disabled.
maintains the last image for several	The projector will wait for about 30 seconds
seconds	before ending projection. You can quit the
	wireless projection immediately by selecting the
	Wireless button on the remote controller.

B-2C400 Wireless Projector: User’s Guide