Verified answer

Yet another glitch on only some of Yahoo's servers? It's been happening for the last couple of days.

'Suspicious activity' means that Yahoo suspects you of spamming.

1.Although the limit for the number of addresses in a mail is 100, frequently your mail is frozen with far fewer. Try sending mails with shorter lists of addresses, and of course use BCC for privacy, sending the mail To: Yourself.

2. There are also limits on the number of mails sent per hour (200?) and per day, so you may have exceeded those limits. The usual action is that you are frozen from sending for 24 to 48 hours, but may still open mails - just wait out the delay.

3. If you already are receiving the scrambled letters 'captcha' image to prove you are a human, your account is already under suspicion. You may have an infected computer which is using your account as a spam bot without your knowledge. To be sure your computer is not infected, run both an anti-virus and spyware/malware scans, updated and separately - even more than one malware scan, or Trend Micro's Housecall for an online a-v scan. (in 'Safe Mode with Networking' is the only truly effective method - click F8 repeatedly when the screen first lights on boot-up, then arrow keys and Enter to navigate.)

http://housecall.trendmicro.com/

http://www.malwarebytes.org/products/malwarebytes_...

http://www.superantispyware.com/

It is happening far too often.

The support is incompetent - they just cut and paste the same answers over and over.

The Yahoo email system is going down the drain .. Time to migrate to gmail full time.

This issue of inability to send email is unacceptble. My send folder has only few email I had sent.

I was working with older email clearing them and ran into this.

The problem is that capcha challenge is not being offered. Email sent from ipad and other Yahoo apps seem to work.

These people at Yahoo are not realizing that people have other options... I am still complaining which means I hope they improve ...

Yeah, what he said. The problem appears to have resolved itself less than 9 hours after we first spotted it for a brand new account. So it's possible the unsophisticated owner had malware. I think it's more likely Yahoo fixed its server. Their one size fits all approach smacks of Google's Youtube copyright software that will mute your audio if even a passing car's radio is playing a tune. It's sad to see an old friend like Yahoo stooping so low and on the skids. Time to change it's domain name to flophouse.com?

This appears to be a new glitch, many people are getting this message. It usually happens if you have sent a lot of mail at once and Yahoo suspect spamming. However currently it is affecting ordinary users.

I HAD THIS PROBLEM, BUT THEN FIGURED OUT THE RESOLUTION!

For some reason, Yahoo thinks that anyone who has an email related to "Occupy WallStreet" (There was a NY Times article a few days ago.) is a spammer. I searched my email for "Occupy", deleted all emails related to "Occupy WallStreet" (then deleted it from the Trash folder), and it suddenly worked! Don't ask why - just try it.

time to move to gmail