If you are attempting to send an SMS and it contains a Unicode character you will be alerted by a warning box reading 'This is a Unicode message' in MXT.
To avoid including Unicode characters in your message, please do not copy and paste your text from other programs, such as Word, into MXT. Where possible, write your message within MXT.
One useful tip to avoid Unicode is to paste your SMS content as 'plain text'.
The character count below the message box will also change to show the number of characters remaining in the Unicode message (the maximum for a Unicode message is 70 characters).
Removing any Unicode characters from the message box will close the warning box and calculate the number of characters for a standard message again.
For more information please see Understanding Unicode characters