Hi M Tipler,
Could you tell if the content your user need to be imported from website are the same? And if it works fine with general website?
And according to your description, your issue is that you do not receive an error message when you try to open the file. The associated Office application starts, but the selected file does not open.
This problem occurs when the following conditions are true:
The server is configured for Basic authentication.
The connection between your computer and the web server does not use Secure Sockets Layer (SSL).
By default, file operations that use Basic authentication over a non-SSL HTTP connection are disabled in Office 2010 and Office 2013 applications.
When Basic authentication is disabled, one of the following events occurs:
The client application uses a different authentication method. This occurs if the server supports a different authentication method.
The request fails (for details about what happens when a request fails, see the list in the "Additional symptom details" section).
For this issue, there are 2 workarounds you can try to solve your problem:
1. Using HTTPS instead of HTTP to access the website.
2. Connecting a web server by using Basic authentication over a non-SSL connection.
To enable Basic authentication on the client computer, follow these steps:
a. In Windows Vista or Windows 7, click Start, type regedit in the Start Search box, and then press Enter.
In Windows 8, hold the Windows key (WINKEY) + F, highlight Apps in the Menu bar, type regedit in the Search box, and then press Enter.
b. Locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WebClient\Parameters
c. On the Edit menu, point to New, and then click DWORD Value.
d. Type BasicAuthLevel, and then press Enter.
e. Right-click BasicAuthLevel, and then click Modify.
f. In the Value data box, type 2, and then click OK.
Note The mapping is as follows:
0 - Basic authentication disabled
1 - Basic authentication enabled for SSL connections only
2 - Basic authentication enabled for SSL and non-SSL connections
g. Exit Registry Editor, and then restart the computer.
You can refer to this link to get more information:
https://support.microsoft.com/en-us/kb/2123563
Hope its helpful.
Regards,