I have a PC at home running on Windows 7, 32-bit.  Recently, when clearing the temp folder (accessible by pressing %temp% on the Run command), I found that the folder has got some foul videos downloaded from Internet. By foul, I mean totally disgusting, of a very, very, very low level (like pornographic, horrible scenes, etc. which I can't mention). This has been occurring quite often. They come after some days even if I delete them.  I have a licensed copy of QuickHeal in my computer, and a full system scan at great depths shows that there is no virus, malware or any other system change. Behaviour Detection is set to highest security. Firewall is also on.  Our computer is accessed only by my father and me. We never visit any foul site, not even Facebook or Twitter or Google Plus. My father visits a travel forum, while I mostly use it for Java programming.  Moreover, the computer has recently started to crash frequently. We've called a mechanic, who could find no error. The computer has got 4GB RAM, yet sometimes everything on the screen freezes and then everything crashes, including Windows. The task bar and start button are not accessible, and mostly we have to power off the computer and reboot it.  The files come only if connected to Internet. We've tested, and not connected the PC to Internet for a month, and no videos had come.  We work on either Opera browser or Chrome. Both these browsers are known for protecting users from malicious sites. We've installed anti-tracking extensions to browsers like  to prevent tracking.  So, why are these videos coming? I feel somebody is bypassing QuickHeal security firewall and accessing the computer. I conduct a full system scan and a backup every week, so I'm not greatly worried for files, but what is it? What can I do to prevent this? How can I know who is accessing the computer by hacking firewall?  N.B.: somebody wanted to mark this as a duplicate to  one. Let me explain the difference. I don't even know till now whether the computer has been hacked or its a virus. Until and unless I'm confirmed it's a virus, it's not a duplicate.
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What should I do if my Windows computer seems to be infected with a virus or malware?  What are the symptoms of an infection? What should I do after noticing an infection? What can I do to get rid of it? how to prevent from infection by malware?   This question comes up frequently, and the suggested solutions are usually the same. This community wiki is an attempt to serve as the definitive, most comprehensive answer possible. Feel free to add your contributions via edits.
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I know this question is looking like an easy question or not a question at all but it's not really easy question. I'm not related to security and anti-viruses and just don't trust every provided anti-virus.  So first question is a real question - Is it OK (safe) to not use anti-virus at all. I know how to use firewall, usually I use only trusted connections and surfing trusted sites. My chances to get virus is really low. Even I've got a bit outdated PC and don't want to pay the performance for it. I can do monthly scans without having one installed - is it OK to be safe ?  If not can you recommend a good free antivirus solution?
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My Windows 10 laptop with an i7 and 16 GB of RAM often gets the fans going full speed when I am not using it. It is a bit slow to respond sometimes when I try to wake it up to check what is going on. Every time I try to open the Task Manager to check out the Details tab and see what is using the CPU, nothing shows up. I'm running as admin, and all tasks are showing. I am guessing the system is hiding what it is working on because it is seen as a "system" task.  What is a good tool to use that will monitor and report what is utilizing CPU? I've used ProcMon before, but I didn't find the output particularly accurate or helpful.  More importantly, how can I stop this from happening? I am quite annoyed that so much software feels the need to do things when my computer is idle. Is there something like ZoneAlarm, but for CPU?
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I have an Early 2015 MacBook Pro running OS X 10.11.6 (the latest version of El Capitan) that as of late had started randomly opening a website with the link fastlauncher.xyz [Thanks John Ramos: wouldn't be a good idea to try going to the link.] It does not happen often.    I have tried:   to use the latest version of Malwarebytes Anti-Malware for Mac; it did not detect the adware.  checking the browser extensions for Safari and Chrome, the two browsers I use; but do not see anything suspicious.  checking for Login and Startup Items, nothing suspicious restarting (I'm getting a bit desperate and maybe it'll work - it didn't) using BitDefender (30-day trial); solved the issue   I have not tried:   using only one browser and seeing whether the adware will go away (hence I am unsure whether it is a system virus or isolated to a browser)   So far, the link has only been opened in Chrome. I would prefer manual removal over a program. Will update this list as I go.
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I need to check the list of files accessed in my computer (ex: yesterday on particular time). Is it possible?   Or   I need to check whether anybody accessed my computer (when I left it unlocked) or not for a particular time.
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I've discovered this yesterday, as it was generating system load on otherwise idle Ubuntu 14.04 Desktop machine.  Today, I've confirmed such behavior also on another Ubuntu instance (17.10 in Virtualbox VM)  The sub-process in command line looks like below ( I've put this as picture below intentionally to prevent askubuntu.com from changing/escaping the content )   For me it looks like exploit/malware. Or at least there is something to hide.  this happens even for url
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Most online games suffer for this problem and there are some  out there to cover this but recently from what I've seen most companies are trying to avoid those programs creating their own system (blizzard with warden, aion with their own checking, etc...) but it is a very difficult case to prevent such ...  Just wanted to say i made another question topic as community wiki specific for posting applications and it is features and the ideas behind this question here is not to list those but instead to know more about what were your attempts, issues along the road and possible solutions, piece of codes if application and so forth.  What sort of protection do you guys use in order to (try to) prevent such acts:   Anti-cheat Software ? (please state which, why and possible problems you faced, for example aion stopped using GameGuard at beta stage due to a huge amount of compatibility problems and complains from their users) Your own code ? (what sort of verification do you usually run to make sure of the bad-faith players, for example speedhack, verify new location against speed+last location, etc...) None, i dont care ? (any personal reason or input you did like to share ?)   Any interesting piece of code related to the issue you would like to post ?  Feel free to rework my text my english inst that great  ?**
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I posted this question on reddit yesterday and I am grateful that someone replied to me. But I wanted to get a second opinion because I still feel a little anxious. I am not sure if this is the right place to post my question, but here it is anyways:  I am an individual who is very inexperienced with computers. Yesterday I accidentally dragged one of my folders, which contained a lot of personal information, onto my Google Chrome browser (I was on google.com), and it looked liked the directory of my folder was readily available on the browser. My question is: did I just upload my personal information onto the internet?  Thank you for any responses.
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A friend of mine downloaded some malware from Facebook, and I'm curious to see what it does without infecting myself. I know that you can't really decompile an .exe, but can I at least view it in Assembly or attach a debugger?   Edit to say it is not a .NET executable, no CLI header.
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I've started getting random blue screens from my (admittedly aged PC). Unfortunately it reboots straight away so I don't get chance to read the error. It's been happening when browsing Stack Overflow in Google Chrome and Firefox so I'm assuming that it's something fairly fundamental.  Most of the time it puts up the "Report the error to Microsoft" dialog and I've checked the data files it wants to send but can't find the information there. I'll freely admit I could be looking in the wrong place.  I'm running Windows XP SP3 and I'm fully up to date with the updates.  The CPU is an Athlon XP 2600+, I've got 2 GB of RAM installed, an nVidia Quadro4 980 XGL driving two DELL 2001FP flat panels at 1600 x 1200 pixels (32 bits/pixel).  I've checked the CPU fan (which has been recently replaced) and that seems to be turning freely. The insides are a little dusty, but not excessively so.  So I need to either stop it rebooting or find out where the error code is stored so I can read it after the reboot.  UPDATE 22/09/2009  OK - just had the BSOD and it's in win32k.sys. I'm doing some research to see if I can find anything that might help. If I get stuck I'll post a new question. Thanks for all the suggestions.
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I work at an embedded software company. This morning I found a USB stick in the parking lot in front of the building. With all the stories of "dropped USB stick attacks" in mind, I'm obviously not going to just plug it into my laptop. OTOH, I'm curious to know whether this was actually an attempt to compromise our systems, or it's really just an innocent case of somebody accidentally losing a USB stick. How do I safely inspect the USB stick without risking exposure?  I'm worried not just about malware and crafted file system images; there's also stuff like power surge attacks:.  EDIT: Many of the answers seem to assume I want to keep the drive and use it afterwards. I have no interest in that at all, I know USB sticks are cheap, and that it wouldn't be mine to keep anyway. I only want to know whether this was indeed a semi-targeted attack, partly out of curiosity whether this actually happens in real life and not just in security papers, but also so that I could warn my coworkers.  I want to know how I would figure out whether the stick contains malware. And that's not just a matter of looking at the drive contents and seeing a suspicious autorun.inf or a carefully crafted corrupt file system - I very much also want a way to inspect the firmware. I sort-of expected that there were tools for extracting that and comparing to known-good or known-bad binaries.
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I'm trying to debug a program which is not logging the information I need. Fortunately, it does write temporary files which should contain the information. These files are written to a directory like: program/temp/{someGUID} on one of ten machines. Neither {someGUID} nor which machine will contain the temp files is known in advance of the run. After the run is complete, the temporary files are deleted. The time from beginning to end is too fast for manual intervention.  I kick off the runs through a client program, but it is the server which writes the files. I am unable to manipulate the server program and once a run is kicked off I am unable to stop it. I do have root access to the all the machines on which the temp files could be written. I'm running CentOS 6.  Is there a way to allow the server user to write files to the temp directory but not remove them? It would probably crash the run, but it would give me the information I need. Is there a way to copy the contents of the temp folder right after they are written/before they are deleted? Must I install a program for recovery of deleted files?
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software_reporter_tool.exe belonging to Chrome running at 100% cpu, fan full speed.  Deleting it doesn't fix anything, because it gets redownloaded again! Disabling "Protect me from bla bla" doesn't make it stop running.  Please anyone have any solutions?
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I am the administrator on my PC. There is another local account on this PC. I just want to know, if I wish that the other will not be able to view D and E drive, then what should I do? How can I prevent the other user from using the D drive?  I have tried the "stop sharing"  from the computer management, but the other user still can open the D drive.  I am on Windows 10 Pro OS.
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I have noticed on several Windows 7 machines that Windows updates and Windows driver search can cause svchost.exe to consume excessive amount of RAM.  In the case of Windows updates, it seems that all the updates get downloaded to RAM, cached, and then you experience the joy of installing them while the machine is operational, and again at reboot.  I have these machines set to never download, update, or notify the user of updates, because svchost.exe, TrustedInstaller.exe, and wau...exe all go haywire under any other setting.  svchost.exe will still consume the massive amounts of RAM under any of other the options for Windows updates.  Therefore, I now manually check and install updates once a week.  in the case of Windows driver search, when you plug in a new device, Windows will consume an excessive amount of RAM while it's probing, analyzing, and downloading a driver for the device.  The most prominent example is when I attempted to connect a 3TB drive to a machine.  My laptop was not able to connect to the device.  It was a Core i7 with 4GB of RAM.  I plugged the drive into a desktop with 16GB of RAM.  I don't recall if this machine had crazy RAM usage trying to cess out the drive.  However, the laptop got an upgrade to 12GB of RAM, so I connected the drive to it.  RAM usage for svchost spiked to 3GB.  I've seen similar, but not as extreme, behavior almost any time I plug in a new device.  These machines are all Core i7s of some variety with 12GB of RAM and up.  Not light specs, though maybe that's only average for 2015?  I have researched this phenomenon before, and while I have found many people asking similar questions, I have not found solutions to the problem.  Is there a way to mitigate this behavior?  Relevant links:
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Lately I see a blue screen of death a lot and want to know why it appears. Where should I gather the information so the problem can be diagnosed best? Couldn't find anything in C:\Windows\Logs.
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In reviewing a post in the reopen queue, I came across the following.        (The review in question is )  I don't see anything jumping out at me as a cause, so it could be browser related (just a wild guess though)  Browser: Chrome 43.0.2357.132 m OS: Windows 8.1