malicious email

Hello my name is ivan my computer skills are basic but i could do with some
help i own a company called stoke workshops for the blind
it as been going for 186 years we are an engineering workshops welding bending
forming metals, all the employees are disabled from blind ,deaf, strokes , heart attacks , learning difficulties , traffic accidents , limbs , the whole works , and the best bunch of guys/girls i have ever met multi talented multi skilled hard working and have all overcome there disabilities ,
a email was sent to our sales office and it was really nasty , on the same day
it was sent to a customer saying some horrible things, i need to find who is doing this can any one help the email was from importantATlondon.com and it was sent to salesATstokeworkshops.co.uk
please can any one help thanks ivan

 

"Mailwasher "

Download "Mailwasher" for free,when installed you can view the emails and decide whether or not to send it to your inbox,the program allows you to blacklist any unwanted mail and will also bounce it back to them,I use it all the time it's fun knowing that you are sending them their own mail.