re temp: turn it down to 300C and wait a few minutes.
then just try to melt a bit of the solder to see how long it takes.
if it's a couple of seconds or longer, then it's too cold turn it up to 350 and wait a few minutes again.
keep trying 'till the solder melts almost instantly.
as D mentioned, too hot, and it fries it before it has chance to flow.
forget about the very point of the tip. there's not much heat there. go for the bit that just back about a 1/8th of an inch where there's more meat n' heat.
use ur iron's tip more so from it's side rather than the point. Then when applying the 'tip' to the job, touch the solder to the tip not the contact, and once the solder melts, u get better heat transfer to the contact and the solder will flow to it.
… or something like that.
…. and always keep wiping ur tip a keep it clean.<script type="text/javascript" src="safari-extension://com.ebay.safari.myebaymanager-QYHMMGCMJR/6f136b72/background/helpers/prefilterHelper.js"></script><script type="text/javascript" src="safari-extension://com.ebay.safari.myebaymanager-QYHMMGCMJR/6f136b72/background/helpers/prefilterHelper.js"></script>