Hi,
I'm pulling this from somewhere else but would try this first,
When you type text that Outlook detects is a link, the text is automatically turned into a link. You’ll usually see this text with an underline.
Usually, this works well. However, if there’s a space in the text that makes up the link, Microsoft Outlook truncates the link at the first space. If the first space is in the network path or location of the file, the link is truncated at that point.
For example, if you type \networkshare\February Expense Report.xls into the body of the message, Outlook converts only the first part of the text to a link, as in the following example:
\networkshare\February
This isn’t a valid link to the file.
To preserve the spaces in your link text, use an opening(<) and closing(>) chevron, as in the following examples:
<\networkshare\February Expense Report.xls> __or __<http://www.contoso.com/finance/February Expense Report.xls>
All text inside the chevrons as part of the link, and the recipient receives the complete link to the file.
You can also insert the link by using the Hyperlink command:
In a new message, click Insert.
In the Links group, click Link or Hyperlink.