Hi, Our company is based in AU and has 2 oversea branches in UK and US. We are considering publish our company OWA 2010 through a single address as mail.contoso.com through a TMG array. Ideally, the TMG array will then check the client's IP address to decide whether redirect user to usmail.contoso.com, ukmail.consotoso.com or just mail.contoso.com. This is to save Exchange 2010 from looking up AD site then decide which site to redirect. For AU users travelled to US or UK, they will be re-directed back to mail.contoso.com. I am familiar with ISA but not TMG. Can anyone see any potential issues in this design?

Hello, You can either configure OWA proxy or redirect according to your production environment and requirement. Understanding Proxying and Redirection http://technet.microsoft.com/en-us/library/bb310763.aspx Considering the TMG settings, we can use the following link to create a new thread via our TMG forum so that you can receive more accurate and professional suggestions from our TGM supports. Forefront for Exchange Server http://social.technet.microsoft.com/Forums/en-US/FSENext/threads Thanks, Simon