Weird email "Message has been processed :Waiting for the payment."

[#1]

Received email on Monday (I don't login every day) supposedly from my email address to my same email address with the above title.

Nothing (visible) in the email itself & I definitely didn't send it (or anything else around that time).

Worried that this is the result of some sort of data breach on my account.

Has anyone else had this &/or can explain it?

(If not can someone in Plusnet please check this out ) Thanks

[#2]

@Wendy101  welcome to the forum.

Its very likely a scammer using your your email address to pretend its from you. Sadly its fairly easy to forge the email address an email supposedly comes from.

I have had several similar to this after the past week. I just delete them and under not circumstance open any attachment.

If you have opened any attachment in the email (say a word document) Then I suggest you run a full virus scan of your computer to be on the safe side. 

[#3]

I agree totally with @wakeman . If that is the same ( or similar) to the two or three I received (and my AV promptly stripped of the payload), you will have been infected. I suggest running multiple scans -and ensuring your antivirus is fully up to date.

I doubt this is a data breach on your actual account - more likely that one of your correspondents has has been hacked.

[#4]

There was no attachment & checking my AV (thanks for the tip), it did pick up & delete something called "HEUR:Hoax.Script.Scaremail.gen".

However, if (at least) 3 of us have had the same thing in the same week, is it possible that scammers have had access to Plusnet email addresses? I can't see anything online for this specific message though the software itself is quite old

[#5]

As @jab1 says its not likely to be your PlusNet account, its more likely one of your contacts has got themselves infected and not cleaned their  computer. Make sure those 3 people you mention also clean their computers with up to date AV software.