Anastasia21

A few clarifications needed.
First, multiple AV/anti-malware solutions can be installed. However only one should have its real-time protection enabled to avoid conflicts. The other solutions should have their real-time protection option disabled. Some solutions will run just fine in this status. Others might constantly complain via internal status display or alerting about their real-time protection being disabled.
The interesting point posted is AVG's detection of an Eset protection module. Granted it was a "suspicious" detection but I would assume AVG is capable of detecting known safe processes/dll's. So let's get back to the original posting where you stated you installed a free version of NOD32. Do you mean that you installed it in trial license mode? Did you download NOD32 installer from the official Eset web site?
Finally, to avoid conflicts with multiple AV solutions installed, the main engine component of each should be excluded from the other solution. For example in AVG, ekrn.exe needs to be excluded from AVG's real-time scanning, behavior monitoring component, web access protection component, etc.. Likewise in Eset, the above AVG protection components need to be excluded from Eset's real-time scanning, HIPS, and Web Access protection components.
Bottom line and again - it is best to only use one AV solution. If others are used, you must disabled all their related real-time and behavioral/HIPS components and only use these solution as on-demand scanners.
 

I'd say it's very light weight and good detection.

I was also wondering the same. No one really answered as to why ESET don't participate in AV tests which it should.