We cannot send a text message to this number.

thank you. your solution worked.

I solved my problem by similar way. I tried to logon to my account by using my Samsung phone's browser.

if you are having this problem with your microsoft hotmail, live or outlook account on your PC suspending your account because you replied to a message that microsoft identified as spam even though it wasn't spam & it asking you to verify your phone number & then it tells you that number can not be contacted.

this is what I did on my windows 10 PC.

clear your cache

log-in to outlook.com

when it asks you to verify through an email address look to the bottom of the window, chose Sign in using a different method, chose send test message to ####
add the 4 numbers, you'll get a code.

hope this helps.
i had to read 1,500 messages on this site which were all 100% unhelpful, especially the one from Janbaz Salehi who told me to log into the account that "i was locked out of" & told to ad my phone number "to the account that I could not log into"

not very forward thinking Mr. Janbaz Salehi

My father had this problem and I was helping him remotely. Could not get it to send a text to any phone number. Tried everything else listed. Finally tried logging in on my computer and it worked. Microsoft is probably blocking your IP address or device (or both) after too many unsuccessful tries. You need to use a completely different device, phone, laptop, etc, or use a VPN, or both. Windscribe is a free VPN service to use. Once you get back in be sure to generate a Recovery Key in your account settings, then use the Snipping Tool to screen cap it. Save a copy to your Documents folder, and take a picture of it with your phone. If you don't have a backup email address, create one and email it to yourself as well. It's all a PITA, but Microsoft won't chat and help you, so you have to do it yourself.

I was havet same problem. I tryied others internet browsers... Not work.. But whem i use my iphone safari browser it work. I go in microsoft pages on my phone; put my phone number and they give me the code.

Sorry about my english. =)

Try signing in to your Microsoft account via Skype. I'd tried every other tip in discussions related to this and I stumbled upon Skype sign in and the same looking dialog box which wouldn't work when trying to sign into Microsoft or Outlook allowed me to enter my phone number and it sent me an access code which unlocked my account.

No idea why but this worked!