How to : Delete email address history

Clearly there are some email addresses stored in "History" in my Wildfire where I have used my linked POP3/ISP email account (i.e. not Gmail, Yahoo mail etc) to send emails. 

I guess the addresses of the recipients have been "remembered" by my Wildfire handset even through they are not and never were in "People", in the same way that recipients' email addresses are remembered by the email programmes of some PCs - whilst the names may auto-fill when typing a new email to a previous recipient, the recipient is NOT automatically added to "Contacts".

Consequently, on my HTC Wildfire, a few email addresses in "History" have become obsolete with time as some of the people have changed their email addresses but the Wildfire wants to send emails to the old, incorrect addresses.

So, how can I delete "History" of email addresses to stop me sending emails to the wrong historical adddress ?

Use "Cache Clear" from Play Store. 

This works.  FINALLY!!!!!