We’ve all done it – inadvertently “replied all” or selected the wrong email address from that handy drop-down menu in Outlook. I’ll admit it – I’ve mistakenly sent a partner a recipe, and my sister instructions about formatting my dictation – although that recipe worked out for everyone involved. My errors were harmless, but in the case of email snafus, this one takes the cake: a manager’s email to the company lawyer seeking advice about terminating an employee was inadvertently copied to the employee in question opening a veritable Pandora’s Box for both the employee and employer

In Fernandes v. Marketforce Communications Inc., the company’s Director of Operations sent an email to the company’s lawyer attaching another email from a manager questioning the employee’s continued employment. The Director wanted to arrange a conference call  and referred to considering termination. The Director accidentally copied the email to the employee.

Immediately realizing her mistake, the Director attempted to recall the email message three times, and eventually sent an email to the employee claiming the message was inadvertently sent and that it was privileged and confidential. She asked the employee to delete the email without reading it. So did this employee do as she was requested and delete the email without reading it? OF COURSE NOT. She opened the email, read it, and copied it to her lawyer.

After taking her previously scheduled month-long vacation, the employee notified her employer that she would not be returning to work and that, after receiving the email, she was left to interpret her employer’s position as terminating her employment. What did she do? She sued for wrongful dismissal.

The Employer fought hard to have the email and its contents kept out of her Statement of Claim and out of the litigation. They based their argument on that most sacred and protected ground at law – solicitor client privilege. If there is anything in the legal world that is nearly untouchable, it is solicitor-client privilege. In order for a document or communication to fall within the protected category of solicitor-client privilege, three (3) prerequisites must be met: (1) it must be a communication between solicitor and client; (2) which entails the seeking or giving of legal advice; and  (3) which is intended to be confidential between the parties.  Only the party who has the privilege (i.e. the client) can waive that privilege.

At an early motion to have the email excluded, the motions judge found that while the email was solicitor-client privileged, it would be unfair to the employee to preserve the privilege, when reading the email affected the employee’s state of mind and made her unable to trust her employer. When making his decision of whether the inadvertent copying of the employee constituted waiver of the solicitor-client privilege, he first addressed the fact that the error was excusable, that there was an immediate attempt to retrieve the communication, and finally, whether maintaining the privilege would be unfair to the employee. The judge held that it would be unfair to the employee to remove the email, because without it, any trial judge hearing the case would have no understanding of what took place.

On review, the Divisional Court upheld the decision, finding that the motions judge was correct and the email could be used against the employer. That seemingly small error has become a big, embarrassing, and rather costly mistake.

Think this is bad? Check The Week’s list of 9 embarrassing “Reply All” email mistakes, including the US Attorney who accidentally attached the wrong document to a media briefing and mistakenly identified confidential sources.

So how does one overcome such gaffes? Check out CBS News’ Survival Guide to overcoming email mistakes at work.

But of course, the best advice is to avoid these problems at all. PC World has 7 great tips on how to avoid these errors at the end of this article.

Or, you can always try just picking up the phone.