dlink dwl-800ap+ repeater mode

i have a dlink di-614+ router connected to a desktop and recently got a
DWL-800AP+ to use as a range extender (repeater mode). however,
whenever i turn it on i cant access the internet with my laptop even
though i have excellent signal strength and appear as connected. when
it is off i am able to access the internet. ive repeatedly asked the
dlink tech support guys for help but none of their suggestions have
worked. i hope someone can help me....