If you are invaded by internet windows, which contain the address indieposts.com, then your computer is infected with an adware. This infection modifies the registered DNS in your network settings in order to place its own. Then, we can talk about DNS Hijack (literally DNS hacking) and its effects can be very serious…
The Domain Name Service (DNS) is actually an internet directory and converts a domain name (e.g. societegenerale.fr) into an IP (here 193.178.154.48). DNS is the most fragile and vulnerable component of the functionality of the internet. The control of DNS returns to the control of internet and nowadays can signify the control of our interlinked world.
A hacker can be interested in DNS mostly as part of a fraud: Imagine that you are connected in a commercial site for an online payment. As usual, you enter the name of the site on your browser and you proceed to the payment. If a hacker can redirect your connection to his site by modifying the DNS data in the DNS server of the commercial site, he can easily collect your payment information such as your used credit card number and go on a big vacation with your money…
Concerning the indieposts.com, the modification is used a priori only for opening of pop-up windows. However, reset your DNS immediately with the help of RogueKiller by ticking in the Registry tab the lines with the mention PUM.DNS.