Wikipedia:Reference desk/Archives/Computing/2013 April 28

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April 28

Antivirus Program

Hey guys! I finally figured out my downloading problem! Turns out it is a fairly common problem when upgrading AVG. It wasn't Internet Explorer's fault at all. All I did was uninstall AVG then reinstall it and I can download anything fine! :) The only problem is, now that I have reinstalled AVG, it has turned into a 30-day free trial, even though I've been using it free for 4 years! So, my question is: is it possible for me to get it to be unlimited again; and if that isn't possible, does anyone know a good, free, unlimited (and reliable!) antivirus program that I can switch to? Thanks! --Yellow1996 (talk) 01:48, 28 April 2013 (UTC)

The 30day trial only applies if you have also enabled any elements of AVG Internet Security such as the firewall. To change it back (In AVG 2012 or 2013) just open Add/Remove Programs, select AVG and CHANGE. One of the options will be to switch to the free AVG Antivirus. Nanonic (talk) 02:29, 28 April 2013 (UTC)

Thanks a million! :) It worked, and now my computer troubles are finally over. --Yellow1996 (talk) 17:35, 28 April 2013 (UTC)

MS Word; do not skip to new page for new paragraph

In MS Word 2010 for PC, when I am writing in paragraphs, if my new paragraph begins on the last line of a given page, MS Word will automatically bump the new paragraph down to the next page as I am writing the paragraph. This leaves a one line blank on the bottom of the previous page. I understand that it is probably doing this to make the formating more aesthetically appealing, but how do I stop it from doing this? Certain paper submission guidelines, for example, want you to have x lines per page and maintain equal margins throughout. It is hard to follow this when Word automatically adds a break to move the paragraph to the next page, leaving a larger apparent bottom margin on the previous page. Acceptable (talk) 04:35, 28 April 2013 (UTC)

Just ignore it. I guarantee you the editors won't even notice it. Looie496 (talk) 04:41, 28 April 2013 (UTC)

Click the Home tab and then click the dialog box launcher in the lower right corner of the Paragraph group. Click the Line and Page Breaks tab in the Paragraph dialog box and uncheck “Widow/Orphan control”.--Shantavira|^{feed me} 07:22, 28 April 2013 (UTC)

Antivirus products

Can an antivirus product detect and remove a virus which got onto a system before it was installed? Clover345 (talk) 16:34, 28 April 2013 (UTC)

Yes, an antivirus program will detect anything and everything malicious/infected that it finds on your computer, regardless of when the virus got there. --Yellow1996 (talk) 17:37, 28 April 2013 (UTC)

Saying that an antivirus will detect anything and everything is kinda too broad of an assertion. Indeed, some antivirus will check what you are downloading, and block these virus. Anyway, most antivirus will only detect what it was programmed to detect, and won't protect against zero-day attacks, unless the program uses some form of heuristics. OsmanRF34 (talk) 18:21, 28 April 2013 (UTC)

The assertion that antivirus software can detect anything malicious is not even close to correct. First of all, there is no widely-accepted definition of "malicious software." In a recent posting, I declared "malicious" to mean any piece of software whose source-code satisfies my regular-expression search for "google" or its aliases - an uncommon, but legitimate, definition of "malicious." Secondly, it is implausible that any software can ever detect everything. This is, in fact, provably impossible - because antivirus detection is computationally equivalent to solving the halting problem, as you will find in nearly any reputable book or paper on malware research - our article links to Len Adleman's work, An Abstract Theory of Computer Viruses (1988). And it is worth pointing to Ken Thompson's famous paper, Reflections on Trusting Trust (1984). Basically, the logic goes like this: for any algorithm you come up with that detects malware, a malware can be designed specifically so that it is undetected by that algorithm. Alternately: for any code you validate to guarantee its safety, a compiler or a host interpreter exists that will surreptitiously convert that sanitized "safe" code into malicious "unsafe" code.

Instead of treating malware by detection-and-removal, there are other security strategies, like hardware-enforced application whitelisting, and cryptographic signature verification, to secure important computer systems. It is my opinion that commercial antivirus software is actually far less effective than simply using common sense, and running only trusted software. Nimur (talk) 21:48, 28 April 2013 (UTC)

Yes, you are both completely right. What I meant to say was "can delete" rather than "will detect" - because obviously an antivirus program can remove something that it detects. To the OP: as stated above, it depends on what program you have and what it has been designed to find (some are meant specifically for Spyware etc), or what you have configured it to find. But the answer to the question is yes - the time that the problem files got onto your system has no effect on whether an antivirus can detect and remove it or not. --Yellow1996 (talk) 00:53, 29 April 2013 (UTC)

There are some viruses which are antivirus aware, and either won't allow the antivirus to run, or will block the antivirus enough that it doesn't permit detection. As each antivirus runs differently, this can be antivirus dependant - the virus may block <popular antivirus>, but ignore, and thus be detected by, <niche antivirus>. The versions of the antivirus also matter. Once an antivirus maker knows there's a program that's subverting detection, they try to block the blocking. - The general rule of thumb, though, is that you shouldn't trust anything that is running on a system that is suspected of being compromised. Once an attacker has access to the core system, they can do basically anything. In those situations, it's recommended to use something like a bootdisk (ideally produced on a known clean machine) to start a known clean version of the operating system, and then scan the harddrive from the clean OS. (To be extra safe, you can change which operating system used - e.g. use a linux liveCD and a linux-based virus scanner to scan for Windows viruses, as Windows viruses typically can't work under linux.) -- 71.35.116.249 (talk) 19:23, 28 April 2013 (UTC)

more blender help?

I recently asked about setting a film as a background in blender, and received some helpful advice, but now I am having trouble again, and following the same advice doesn't seem to be working this time. so I wonder if anyone here knows what to do. I've got the film set as the background texture ok, but I can't see it at all while working, which makes it pretty much useless, any idea how to set it so an image/movie texture appears outside of renders, so I can see it while I'm working over it?

thank you,

213.104.128.16 (talk) 23:49, 28 April 2013 (UTC)