Web Client - Import data from file not supported??

Hi

Im doing a report that lets the user choose the .csv file from the computer and then it imports it to journal table.
It works fine on regular client but when I try to use the same function in the web client I get an error when clicking (...) assistedit button.

The error I get is:
"The operation cannot complete because it uses a feature that is not supported (.NET Framework Interoperability.)"

Is it not possible to use file import from web client and if it is possible can you tell me how to fix this problem?

Thanks