How to inspect data for malware before restoring it

I have a home wifi with 4 Windows computers. A little over a week ago, the emails we sent out started being rejected because our ip address is being blocked by Spamhaus’s Composite Blocking Service (CBS) because we were infected with Trojans/bots/malware. Here is an excerpt of what I get when I look up our ip address on their website:

 

IP Address 72.168.176.105 is listed in the CBL. It shows signs of being infected with a spam sending trojan, malicious link or some other form of botnet.

It was last detected at 2016-08-01 19:00 GMT (+/- 30 minutes), approximately 3 hours ago.

 

So far the website has always listed gozi, conficker, or ZeroAccess as the offending malware.

 

I’ve used various anti-malware scanning tools to try to detect the problem including McAfee, Microsoft Malicious Software Removal Tool, TDSSKiller, Norton Power Eraser, and Sophos Virus Removal Tool. None of them have been able to detect a problem.

 

Besides the reports on Spamhaus about why my ip is blocked, I don’t have any way of detecting whether I am infected until I notice that we are probably using about 1-2 gig of downloads per day more than usual, and then I notice that my administrative rights to the computer have been taken away from me by the malware.

 

I have restored the PC’s to their factory condition, and everything is fine with CBL for a while, but when I start copying data from backups (mostly from USB sticks) I start getting problems listed in CBL again, which is my first indication that something is wrong.

 

I am using Panda USB vaccinated USB sticks and my computers are vaccinated as well. Naturally I scan the data with McAfee (mostly pictures and email files) before I reload it, but it never detects a problem.

I’ve tried seeking advice from local consultants but so far I haven’t found anyone who can help me.

 

Is there any kind of rigorous malware scanner that you would trust to use on the files before copying them to a clean computer? Is there anything better than Panda USB vaccine? I’d be very grateful for any advice.

I've unplugged my router and modem and then plugged it back in. I wiped my disk and reinstalled my computer to factory settings and even before copying any of my data to the refreshed computer or installing any new software or visiting any websites, I checked with Spamhaus and it is still reporting that my refreshed ip is trying to send data to a Command & Control Center and that it is blocking my ip again after it had been cleared. I suspect my router has been infected now and my plan is to reset it to factory settings and start all over again with a yet again reinstalled PC. Has anyone had any experience with malware this pernicious before and does anyone have any advice on what to do about it? Thanks for any advice.

Best bet now is to repost this info with an FRST log fro the Guide below.. We can get a much deeper look in here.

Start at step 6..
Please follow this Preparation Guide and post in a new topic.
Let me know if all went well.

Thanks very much for the reply. I downloaded and ran FRST without a problem and will be re-posting with updates as a new topic. Should I post it to this forum or to the one that is reserved for logs?

Never mind my last post. I see from the directions in the Preparation Guide that I should post it in the Removal Logs Forum.  Thanks again for your response.

You're welcome!!

new topic
http://www.bleepingcomputer.com/forums/t/622472/brand-new-pc-infected-with-bots-s-gozi-confickerzeroaccess-frst-logs/

Now that your log is properly posted, you should NOT make further changes to your computer (install/uninstall programs, use special fix tools, delete files, edit the registry, etc) unless advised by a Malware Removal Team member, nor should you continue to ask for help elsewhere. Doing so can result in system changes which may not show it the log you already posted. Further, any modifications you make on your own may cause confusion for the helper assisting you and could complicate the malware removal process which would extend the time it takes to clean your computer.
From this point on the Malware Removal Team should be the only members that you take advice from, until they have verified your log as clean.
Please be patient. It may take a while to get a response because the Malware Removal Team members are very busy working logs posted before yours. They are volunteers who will help you out as soon as possible. Once you have made your post and are waiting, please DO NOT make another reply until it has been responded to by a member of the Malware Removal Team. Generally the staff checks the forum for postings that have 0 replies as this makes it easier for them to identify those who have not been helped. If you post another response there will be 1 reply. A team member, looking for a new log to work may assume another MRL Team member is already assisting you and not open the thread to respond.
The current wait time is 1 - 3 days and ALL logs are answered.
If HelpBot replies to your topic, PLEASE follow Step One so it will report your topic to the team members.
To avoid confusion, I am closing this topic.