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Then select Squirrel Mail to manage your email.
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Once you select SquirrelMail, select Options.
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Then you will see this screen, select Personal Information.
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Finally, in Signature you have to type the content of your signature and check "Use Signature".
To save the changes, click on "Submit"
To save the changes, click on "Submit"
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This is how you will configure a signature for Squirrel Mail in the webmail.