Follow these steps to stop creating hyperlinks for an E-mail address.

In Excel 2010:
- Go to the File menu and click on Options.
- Now click on Proofing in the left column.
- Now click on AutoCorrect Options.
- In the AutoCorrect box, click on AutoFormat As You Type tab.
- Now uncheck the box of Internet and networks paths with hyperlinks.
- Now click on OK twice.

In Excel 2003:
- Click on Tools menu.
- Now click on AutoCorrect Options.
- Now you see Autoformat As You Type tab.
- Now clear the check box of Internet and networks paths with hyperlinks.
- Now click on OK.