Some of my emails fail " SMTP error from remote mail server after end of data: 550 Messages should have one or no Date headers, not 2."

Some of my emails are rejected " SMTP error from remote mail server after end of data:     550 Messages should have one or no Date headers, not 2."

This happens with only certain email addresses, but always the same ones. I was able to send to these addresses a month or two ago.  Is there something wrong wit the email templates causing this?

Hello,
what version of eM Client are you running?
What mail account does this happen on?
Can you copy the full Log from the Operations window next time this error message pops up?

Regards,
Olivia

Running latest 7.0.26482.0 windows 10 64bit
it happens on both my accounts, which are outlook.com accounts
It’s not a popup window, its an email reply from the mail server, so the log wont be much help.

Hi Olivia,

I was able to send and receive email from one email id but suddenly since Saturday I get this below msg

 v=2.1 cv=M43tU3Es c=1 sm=1 tr=0 p=S6WMyq9UAAAA:8 a=Ay+l1pMk9x6MiSDKRIkPtQ==:117 a=i4Ji9IZezwXASCZYebORTQ==:17 a=L9H7d07YOLsA:10 a=9cW_t1CCXrUA:10 a=s5jvgZ67dGcA:10 a=9+rZDBEiDlHhcck0kWbJtElFXBc=:19 a=GW1xBdLrtEIA:10 a=D_8W1ba7AAAA:8 a=pGLkceISAAAA:8 a=qOHdd0_TAAAA:8 a=ZyTy6xOxAAAA:8 a=gP0l_qnBAAAA:8 a=IS5g4A68AAAA:8 a=Eou7vcXFAAAA:8 a=v0zN4yc7AAAA:8 a=h22UyFJDAAAA:8 a=1M4DpLKgAAAA:8 a=wk7Gq7ydAAAA:8 a=RgBw9RmQAAAA:8 a=_6GpL_ENAAAA:8 a=aix_TVZGeQK6EOadl5IA:9 a=QEXdDO2ut3YA:10 a=dXPh-PITinUA:10 a=1XWaLZrsAAAA:8 a=_Sa17bo1bbg3Y5lzBiMA:9 a=wjTtLtirv28hbGVK:21 a=_W_S_7VecoQA:10 a=5fYMMchKDoWQE6Ttrd8A:9 a=fMZ_E1CIlfQA:10 a=AN4WzCgUKHu0STQrmg9o:22 a=RYajCwZdUouXZKHJCHGh:22 a=6kGIvZw6iX1k4Y-7sg4_:22 a=vVpKxAVW8K0jXHAAUFrV:22 a=cf7c9vWptBBNL8bI6Zzc:22 a=lfanuOr7k6PVYlnT3HSu:22 a=gNljcNr-Obxg7qlJ2Vqp:22 a=SuqaLv6R05P1CvbKdd

Please help
Regards
vinod.samson@greensoftlabs.com