>>>I get an annoying message from Comodo (personal fire wall) that RegScan.exe (IP: 71.243.0.12 Port: DNS(53) UDP) is trying or modifying IEXPLORER.
>>>
>>>I can't seem to find a consistent info if this is a legitimate program of Windows OS or a spyware.
>>>
>>>Can anybody make suggestions?
>>>
>>>I found a utility on UniBlue RegistryBooster site that is suppose to clean up the registry. But I don't want to run it unless I know it won't do some harm.
>>>
>>>I use AVAST personal anti-virus.
>>
>>That IP address is public; nslookup reports it is nsbost01.verizon.net. Is that you? If not, someone else may be port scanning or probing your computer, possibly with a spoofed IP address.
>
>I am on verizon DSL and I am in Boston area but I don't know if this is my IP. How can I find out? When I run IPCONFIG I get IP of my Linksys router (192.168.1.101).
>
>Thank you.

Go to http://www.dnsstuff.com/ - it will show you what IP address you are using just below the black title bar (light grey). You can also go to http://www.ip2location.com/ and it will show you the same info.

iro RegScan see these:

http://www.file.net/process/regscan.exe.html

http://www.liutilities.com/products/wintaskspro/processlibrary/regscan/

http://www.processlibrary.com/directory/files/regscan