Problem With PDF attachments from External Adresses

Hi there,

I am facing a strange problem with email attachements in my company. We have 2 offices, one in Dubai and in UK. Dubai office uses 'username@dubaioffice.com' and UK uses 'usernameukoffice.com'. Here is the problem that i faced

When a customer sent an email with a PDF file attachement to 'ceo@dubaioffice.com' and a CC to 'secretry@ukoffice.com', the dubai user cannt open that attachement, but the UK user can open the attachement !.

When the dubai user trying to preview the attachement the following error occured

"This file cannt be previewed because of an error with the following Previewer
Adobe PDF Preview Handler
To Open this file in its own program, double-click it"

When Double-clicking, following error comes in adobe reader.

"Adobe Reader could not open 'xxxx.pdf' because it is either not a supported file type or because the file has been damaged (for example, it was sent as email Attachement and was not correctly decoded) "

Cannt open attachment both with OWA and Outlook 2007

After this problem faced i requested the uk user to forward the same email to the dubai user. and this time, Dubai user can open that PDF file without having any problem !.

Both UK and Dubai office uses the following configurations

1. Microsoft Exchange Server 2003
2. Microsoft Outlook 2007

The second problem is

when a user in dubai office, letus say 'secretary@dubaioffice.com' sent an email with five PDF file attachement to an External email address, the recipient recieved only one PDF File instead of 5. all other 4 files lost. then i told the user to sent the same email to me 'admin@dubaioffice.com', i received that email with all 5 attachements!

Please help me to troubleshoot these two problems.. thanking you for rewieving