Published: Nov 09, 2010 6:11 AM EST
Updated: Nov 09, 2010 12:13 AM EST

COLLIER COUNTY, Fla. - It's that time of year... people mailing and receiving packages, leading up to the holidays. If you're doing either than you definitely want to pay attention to this warning.

Emails disguised to look like they're coming from delivery services have already tricked dozens of people and invaded their personal information on their computers.

Basically, you receive an email saying a package had a problem making it to your house. The email tells you to click on the attached invoice and bring it in to pick up your package. But, as soon as you click the attachment you've opened yourself up to a virus.

"The people on the other end can spy on what you're typing. It'll give them indications such as passwords for bank accounts or credit cards. Don't click on something that says we have a package for you whether it's from the Unites States Postal Service, FedEx, or UPS," USPS Postal Inspector Doug Smith warns.

The postal service says they are investigating the source of these emails. Some customers have also reported receiving similar phone calls.