Have you faced it ever before?

I think that he/she used a site, or if you wonder about it just try to search it on the search box. Maybe they have the answer.

Well, probably the person who sent you the message, concealed their number. From what I can assume (if you write Telecom I think you're Italian), you should know that if the phone dial * 67 #, hide your number on a call and then the sender can not go back to you. However, I did not know you could do it even with sms

Hi, In our country, calls from embassies has no caller ID reflected on the phone with caller ID capability. Maybe the same setting is used where the number can be hidden and cannot be traced back. Actually, I found one in my SMS setting where I can hide my number from the recipient. I activated it once just to see if it works but it seems not. They can still see my number with the message I sent.

Hi friend, i never received such kind of sms, for the first time i am hearing about a sms without the sender number, i know we can hide our caller id while calling others, but i don't know that we have this option in sms too

I also experienced the same no information call. It was when my Sister called me from Europe, sometimes long distance call will appear in an unknown number because it has a different phone network than your local SIM Card provider. It also is an effect of bad network reception, causing a glitch to the numbers over the cellular phone.

I think it is in the cell phone setting. remember the incognito setting where you can hind your number? I guess that was it. But I am not saying I am sure.To receive SMS without a sender's number is annoying, disturbing and alarming. That shoul dbe stopped.

I also revived several messages from many strangers but the thing is that I could contact or locate the number from where I receive messages. I think such messages are sented by our friends from some sites, which offer free message sending facility.