Znuny and ((OTRS)) Community Edition

I had download the file of CustomerUserImportExport-1.10.0.opm, but I can't extract it. The error message is "Can not open file CustomerUserImportExport-1.10.0.opm as archive".

I would like to import customer data from CSV file, but I can't find any import function in OTRS. Please help!

yaya, the problem is come from firewall setting, thanks.

I had installed OTRS Windows Installation 3.2.11 in my pc, I use IIS and MYSQL database.
I can run the OTRS in my pc as the link is http://IP/otrs/index.pl
but I failed to run it at another pc.
May I know how to configuring OTRS on client computers to connect to my pc?
Please help!