yahoo does not remember my yahoo-mail-id

sometimes and or repeatedly(after a time where the problem solved itself) only yahoo forgets my mail-id(europanorama). i have winme and no problems at all besides that. since 3 months when i started using netscape messenger instead of outlook(no deleted) i had no virus or warnings anymore! i have p166 mmx only, 128 mb ram 4.2 gb hd. i surf a lot.i use webwasher, spyblocker, ad-aware, reglean(microsoft) and regcleaner, norton system works. alltogehther fantastic tools. i have a firewall(norton)