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Win XP. Any browser (Firefox, Opera) cannot open several antivirus sites:

  • eset.com
  • drweb.com
  • freedrweb.com
  • avira.com
  • bitdefender.com

(but usual sites are all OK opened.) I checked: hosts file is clean; ping for AV sites doesn't work too (all packets lost); inet connection to these sites ok from another PC; Windows safe mode: all is OK, sites work.

I have ESET Smart Security on this PC. I performed full check with:

  • DrWeb CureIt (I could copy it from another PC),
  • Avira (could copy it too)
  • MS Sec Essentials.

No resuts. What can be a reason?

marked as duplicate by gronostaj, Ƭᴇcʜιᴇ007, Scott Chamberlain, Tog, emgee Dec 29 '13 at 12:20

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • Sounds like it could be malware. What other symptoms is the PC exhibiting that make you think virus? – Lee Harrison Sep 19 '13 at 13:37
  • I soo no usual symptoms, e.g. infected files, lost files etc. Only can't open AV sites and can't update ESET SS because of this. – RProgram Sep 19 '13 at 13:47
  • I'd try using Microsoft Security Essentials. They tend to work well and are free. If you can't access that website, I'd download it on one PC and copy it over. microsoft.com/en-us/download/details.aspx?id=5201 – Lee Harrison Sep 19 '13 at 13:57
  • @Lee, thanks-- I tried MS SE also 2 days ago. No results on full check – RProgram Sep 19 '13 at 13:59
  • have you checked your HOSTS file to make sure it hasn't been altered? – Lee Harrison Sep 19 '13 at 14:30

Your system probably is compromised. It might be infected.

There are some ways to fix this:

  1. Boot into safe mode (when you boot up, before the Windows boot screen appears, press F8, and enter safe mode from there). Then, go online and install Malwarebytes Anti-Malware (the free version). Update it, and then do a full scan on your computer. Remove any threats found.

  2. Find some rescue disks online that you can boot into and scan your computer with. Many companies provide boot disks, but for most of them, you have to download their antivirus software and install it from there. If the software is paid software, just do a trial. (ESET has a boot disk, but it requires Windows AIK, and there's no point in getting it if ESET can't catch the threat itself normally). Kaspersky, Avira, Avast (maybe), COMODO, Bitdefender, etc. all provide rescue disks (however you need to download the antivirus product first). (Bitdefender installs the rescue boot into your system so you don't need the disk).

  3. If you have another computer, you can download some antivirus software from that computer, and then copy it (by USB, server, etc.) onto this infected computer. Then, update it (if not blocked by the virus) and perform a full scan. Products like AVG only have one scan option (computer scan), so just use that. Try different products if necessary. Kaspersky and Bitdefender are the most recommended because they are the top antivirus companies in the world (Check antivirus ratings at av-test.org).

  4. If none of those options work, you can research about the virus yourself, boot into a linux CD, and make changes to your system there.

  5. Do a system restore (if you can). Search "system restore" on the control panel, and if you have some restore points, pick a good one, and restore your PC.

  6. If none of those options work: a. If you can live without going to those websites then don't do anything. b. Otherwise, backup your data and reinstall your OS.

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