Assuming that you are using Microsoft Outlook as your e-mail program, you can do this by using one of Excel's 'hidden' commands. The command is named "Send to Mail Recipient" and you'll find it in the Commands Not in the Ribbon list while customizing the Ribbon or Quick-Access Toolbar.
For instructions on adding 'hidden' commands to the Quick-Access Toolbar, see the video lesson: Expert Skills Lesson 4-16: Use Speak Cells to eliminate data entry errors.
The Send to Mail Recipient command offers you the ability to "Send the current sheet as the message body". This will send only the currently selected sheet as part of the body text of an e-mail.
This might be exactly what you're looking for, but I suspect that you'd prefer to send each sheet as a separate Excel Workbook.
Unfortunately, there isn't an easy way to split each worksheet into a separate xlsx file and attach them to e-mails. If you want to do this, you will have to manually copy the worksheets into new Excel workbooks and then attach them individually.
If this was something that you needed to do regularly, you might be able to speed up the process by recording a macro.
Recording macros is covered in the video lesson: Expert Skills Lesson 9-10: Understand macros and VBA.
If you need any more assistance, please feel free to reply.
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