Outlook has just started sending all messages in a column 30 characters wide. I cannot find a reason for this
Messages are being received perfectly.
Does anyone know where I can go to correct this please?

Further to this I can write an outgoing email using the full size of the page. When checked in Print Preview it looks fine. When I send it the copy in the Sent folder also looks perfectly normal, yet when I send it to another of my email addresses it is received 30 characters wide. All other emails ae being received perfectly.
I've gone through everything in Outlook to find the cause, including changing the margins, giving a small or larger page, but nothing works. I'm totally lost on this one. Any help would be appreciated.

I've now solved the problem. I went into Tools>Options>Mail Format>Internet Format>Plain Text, which for some reason was set to 30 characters. I've now increased this and all is well. Many thanks