With TeamViewer you can remotely control any computer as if you were sitting right in front of it - even through firewalls. Your partner just has to start a little application which does not even require an installation or administrative rights.
TeamViewer is a very secure solution. All versions feature completely secure data channels with key exchange and AES (256 Bit) session encoding, the same security standard used by https/SSL.
TeamViewer comes with integrated file transfer that allows you to copy files and folders to and from a remote partner - which also works behind firewalls
The major difficulties in using remote control software are firewalls and blocked ports, as well as NAT routing for local IP addresses.
If you use TeamViewer you don't have to worry about firewalls: TeamViewer will find a route to your partner.
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