Q: Asp.Net : How to provide email preview for the different email providers In my asp.net application I need to show the email preview of created email, like with gmail the email will display some different formatting & with hotmail it will some different formatting...

So, How to provide email preview for the different email providers like gmail, hotmail rediffmail etc...

Is their any tool with which I can render in my application?

A: How about an external service such as Litmus App (http://litmusapp.com/)?  They have an API which may also be of some use.

A: To be honest, the only truly reliable means of doing this (and the way we use for in-house QA at the ad agency where I do my day-job) is to have a handful of test email accounts (one on Hotmail, one on Yahoo!, one on Gmail etc) and send a test email to each.
You can mock them up, but they won't be 100% reliable, particularly if you need to deal with batshitcrazy clients like Lotus Notes. Litmus looks like a good second-best.
If you really need to do the preview within your app and can't call out to an API, the best you can realistically manage is to inspect the HTML and CSS of each client (Gmail, Hotmail, Yahoo! etc) and generate an HTML preview inside their page chrome and stylesheet. But I'd strongly recommend against that — it'd be a lot of work and would need constant checking and updating.
Your best bet genuinely is the dull and tedious method of sending it to a test account on each provider. Sorry.
