DWA : " & ' mark converted to ? mark

Guys,

Need your opinion on my case.

User draft an email using Micros0ft W0rd then he/she copy the text and paste it into new memo on webmail. Upon paste the text, all data still intact. But upon she send the email, all " mark and ’ mark will convert into ? mark.

Upon tested, its happen to all users. Its only happen on webmail. Client is working fine.

Please help.