The file g4sip.dll belongs to Adphone, an ad-supported VOIP (voice over internet protocol) service. You can download and install the Adphone software free, and it allows you to make a certain number of ad-supported called before you start to accumulate charges. This file is a dynamic link library, which means it contains parts of code and instructions that the program doesn’t constantly need.
An error with this file means that the program attempted to use the file and Windows was unable to find it. This problem can often be repaired simply by cleaning your registry. The registry is how Windows tracks all the files on your computer, and cleaning your registry just means making sure that everything in the registry is correct. Sometimes the location of a file changes, and the registry loses track of it.
Rather than manually edit the registry, something even Windows experts avoid, just run ZookaWare PC Cleaner. ZookaWare PC Cleaner is designed to find and fix mistakes in the registry, leaving you to get back to the important stuff.