When to Response.Redirect after database insert or smtp email send?

Hi,
I am working on this project at the moment and I have a page where a user can do the following:
Select an email template (page posts back and displays html email in tinyMCE)User then selects email recipients from Gridview (page posts back for each recipient added)Email Recipients are added to another Gridview where there is a remove button columnUser can then click send to send email to all recipients selected.Now I am clueless to this, am I to redirect to another page after successful/unsuccessful email process?
Can I avoid double postbacks without page redirection?


Thanks,
Tris


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