SYMPTOMS
You export objects in AxCMS.net (e.g. Users) in CSV format:

And you get after long waiting all the data just shown in a popup-window and not saved as a file.
CAUSES
CSV-Export is configured this way.
SOLUTION
Configure the export to open a Save Dialog. For this you need to open web.config of the Management System and add SaveDialog=true option as shown here for the corresponding type:
<ExportDefinitions>
…
<Xslt Type="Axinom.AECMS.UserManagement.AxUser"
MimeType="text/plain"
FileName="admin/ExportDefinitions/UsersToCsv.xslt"
AxID="AxUsersToCsv"
SaveDialog="true"
Extension=".csv"
Description="CSV" />
MORE INFORMATION:
As you see above, you can also configure the default file extension (.csv) and the name of the format shown in the export drop down in MS (“CSV”).