The best replacement for outlook express is outlook.

The best alternatives to outlook express are rated as following:
★★★★★  outlook
★★★  thunderbird
★★★  windows mail
★★★  microsoft outlook
★★  the bat
★★  windows live mail
★★  outlook 2003
★  live mail
★  outlook 2007
★  gmail
★  windows live
★  hotmail
★  mozilla thunderbird
★  outlook 2013
★  outlook 2010
  internet explorer
  yahoo mail
  lotus notes
  outlook 2000
  outlook which is better
  microsoft mail
  vista mail
  web mail
  ms outlook
  outlook 2002
  windows vista mail
  office outlook

Your alternative for outlook express is not listed? Suggest!
Speaking about outlook express, one probably shouldn't forget about gmail.

Other search terms related to outlook express and their ratings are:

★★★★★ gmail
★★★★ yahoo
★★★ hotmail
★★ yahoo mail
★★ exchange
★★ aol
★★ opening
comcast email
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yahoo mail settings
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yahoo mail plus
windows live mail
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yahoo plus
You have in mind a companion for outlook express and it is not yet here? Propose!

Google Trends

Scale is based on the average worldwide traffic of outlook express in all years. Click on graph for more.
outlook express