We have one computer on our network that continues to have problems opening attachments in e-mail or on our server.  if we follow these instructions it works...temporarly and then we must do it again 2-3 days later.
 
    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WebClient\Parameters
    On the Edit menu, point to New, and then click DWORD Value.
    Type BasicAuthLevel, and then press Enter.
    Right-click BasicAuthLevel, and then click Modify.
    In the Value data box, type 2, and then click OK.
 
    Note The mapping is as follows:--WE SET THIS TO 0
    0 - Basic authentication disabled
    1 - Basic authentication enabled for SSL connections only
    2 - Basic authentication enabled for SSL and non-SSL connections
 
 
After we do the above it works flawlessly, however today instead of 0 we had to use 2.....
 
Any thoughts?