What is mscorsvw.exe? Is mscorsvw.exe spyware or a virus?

How to fix mscorsvw.exe related problems?
1. Run Security Task Manager to check your mscorsvw process
2. Run Windows Repair Tool to repair mscorsvw.exe related Windows Errors
3. Run MalwareBytes to remove persistent malware

Process name: .NET Runtime Optimization Service or Microsoft .NET Framework or Microsoft Common Language Runtime Service Host

Product: Microsoft .NET Framework or Microsoft .NET Framework NGEN

Support: Help link   Update link   Uninstall tool  

Company: Microsoft (microsoft.com)

File: mscorsvw.exe

mscorsvw.exe is part of the .NET programming language from Microsoft. This file is used by programs that make use of .NET. If you do not have any programs that make use of .NET you may safely stop and remove it.http://www.neuber.com/taskmanager/process/mscorsvw.exe.html 

If you want a detailed security rating about your mscorsvw.exe (and all other running background processes) read the following user opinions, and download the free trial version of Security Task Manager.

Note: Any malware can be named anything - so you should check where the files of the running processes are located on your disk. If a "non-Microsoft" .exe file is located in the C:\Windows or C:\Windows\System32 folder, then there is a high risk for a virus, spyware, trojan or worm infection! Check it out!

Click to Run a Free Scan for mscorsvw.exe related errors

Users Opinions

Average user rating of mscorsvw.exe: based on 67 votes. Read also the 40 reviews.

  • 1196 users ask for this file. 30 users rated it as not dangerous. 12 users rated it as not so dangerous. 12 users rated it as neutral. 8 users rated it as little bit dangerous. 5 users rated it as dangerous. 7 users didn't rate it ("don't know").

All comments about mscorsvw.exe:
Runs every 10 - 16 minutes for about 4 to 12 seconds. When it runs, it locks up Outlook, closes open screens, cancels scrolling, interferes with other processes. A real PEST! Zone Alarm seems to stop it if you "Kill" it in the program control screen. (run block) Roger S. Orlando, Fla.
mscorsvw.exe is precompiling .NET assemblies in the background. Once it's done, it will go away. Typically, after you install the .NET Redist, it will be done with the high priority assemblies in 5 to 10 minutes and then will wait until your computer is idle to process the low priority assemblies. Once it does that it will shutdown and you won't see mscorsvw.exe...  See also: Link kerttu
hohe cpu auslastung lucutus
it is used to run certain apps created by the framework.it doesnt seem hamless at all. sean
When it is active it takes up a large amount of memory (I had it in excess of 100 MB)
mscorsvw.exe is precompiling .NET assemblies in the background. Once it's done, it will go away oleg
mscorsvw.exe is precompiling .NET assemblies in the background. A good info (including get rid of mscorsvw) is the Webblog from David Notario.  See also: Link Hauke H., Germany
mscorsvw.exe is precompiling .NET assemblies in the background. Once it's done, it will go away. Typically, after you install the .NET Redist, it will be done with the high priority assemblies in 5 to 10 minutes and then will wait until your computer is idle to process the low priority assemblies. Once it does that it will shutdown and you won't see mscorsvw.exe. One important thing is that while you may see 100% CPU usage, the compilation happens in a process with low priority, so it tries not to steal the CPU for other stuff you are doing.  See also: Link Mimo
Runs while installing Live services using the Windows Live Installer Dashboard, no threat. Dave
mscorsvw.exe = Microsoft .NET Runtime Optimization Service, attempts to connect to, OBserver
to remove, uninstall update KB974417 for microsoft.net framework 2.0
.NET pretends to have finished installing but runs this instead as noted above. Bloody annoying, why not just do it all at once, and let us wait for the install to finish - if I want to do a system backup, I now have to back-up this in a half-done state. Microsoft strikes again with their 'logic'... Not dangerous except to waste your time. Obgeektor
like most compilers, it takes too much cpu
it runs without permission by the user, uses up CPU and RAM. wolf
My anfti - virus says it's infected and has it quarantined Gary Overton
.Net application, basically useless, but it does it's job (still useless) Poofy
Run services.msc . Select the service - Microsoft .NET Framework NGEN v4.0... , go to its Properties and choose Stop and Manual. If you use VS 2010 then run this service just before. Tada!  See also: Link dual_barrel
Along with sethc.exe and Flash\uninstall_activeX.exe it is a possible host for the FakeAlert trojan  See also: Link Random Arrow
Precompiles .Net assemblies in the background. This has to be done after a reference changes (e.g. by update or service pack install). To get rid you have to call 'ngen.exe executequeueditems' which precompiles everything in the foreground. After it is ready, the programm will vanish from taskmanager.  See also: Link slompf
To fast forward (force) the compiling to complete as fast as possible and make this process permanently go away: (A) Open a Command Prompt as Admin (Right-Click on Icon and "Run as Administrator", (B) Type in "CD C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727" and push ENTER , (C) Run this command "ngen.exe executequeueditems",(D) Type in "CD C:\WINDOWS\Microsoft.NET\Framework64\v2.0.50727" and push ENTER , (E) Run this command "ngen.exe executequeueditems"  See also: Link Jason Tram
not dangerous but loads of cpu. ive found if you go to internet options, advanced settings, security - uncheck the box: check for certificate revocation (this has never done anything useful for me whilst being ticked anyway). After unchecking this option/apply/ok i found it goes away for the most part and if it does come back at least its not there all the time hogging resources like it was! bloody MS again tut. Goodluck corinne
it eats my cpu and slows the computer terribly Steve Horsfall
.net framework Compiles in the background to speed up useless .net framework software, but slows down everything else Frank White
mscorsvw.exe optimiert .net anwendungen for der laufzeit, führt temporär zu hohen cpu auslastungen. Die Last verschwindet aber wieder. apfel
It runs only for a limited period of time. On my PC it uses less than 10% of CPU and about 50-70 Mb of Ram. I recommend you leave it alone. It's safe. adser
Look at this link  See also: Link Geek_10
Well, I turned on my computer this morning, and upated Windows 7 SP1 Ultimate (x64) like I do everyother day, and lots of .NET updates were installed. I rebooted and now 1 whole core of my dual-core Pentium D is constantly taken up. My PC can easily handle Skyrim normally, but now even games like World Of Warcraft lag. I have never encountered this on any Windows machine, and i fix them daily. PwnHkr
it about framework 4 update in MS ..I think so as well. OS win7 not need NET 4 at all.. never install NET 4 before and the above process don's show up jason tram2
It starts up with my computer and uses a lot of cpu but after a while it uses only 0% cpu. it's from the .net framework.
only runs for a very short time after a os update. Let it connnect to the internet to finish up whatever the security update was doing. I haven't seen it try to run/connect again. James Cseh
on older machines it can eat cpu usage/ram similarly to malware or a virus. It will go away if you leave it alone for a bit, but don't bother keeping it of you don't use the .net framework for anything. someone else posted removal steps. OverheatedWraith
Depending on how fast your computer is, and how many programs you're running in the foreground, MSCORSVW will finish its optimizations and then close or move to a background process using virtually zero cpu cycles. It's not entirely necessary and can be disabled from running, or you can just let it do its thing and that would be the end of it once its complete. It's not dangerous at all, tho I wouldn't say its not possible for someone to mask malicious code in the process - known safe mscosvw.exe file should only be found in the .net framework folder, nested inside the Microsoft.NET folder , inside the main Windows folder, be it 32 bit or 64 bit.  See also: Link Jim Bob
It is a very anoying program. It stalls my computer and eats a lot of CPU time and memory. It would be much better if would be in control starting this program when I like to put my computer on idle Henk van Kampen Netherlands
It wants to access the following IP's in this process, most owned by akamaitechnologies,,,,,, and many more - thanks to ZoneAlarm. Don't see the need for Akamai and the .NET framework, as it claims it for improving performance... Thanks MS or is it Akamai Mike
its harmless really , if only runs in the background for a short time to compile and speed up old ,NEt frameworks once its done its job it will stop taking all your CPU cores , its only dangerous if its not located within the windows/.NET framework folder Rokeugon
To get rid of mscorsvw without breaking anything: Hit start, type "cmd", press Ctrl+Shift+Enter to start a command line in Administrator mode. Then "cd \windows\Microsoft.NET\Framework\vx.x.xxxx" (use the highest number) and type "ngen executequeueditems". This will do all the work that mscorsvw is supposed to do. It may take a while, but then its done and doesn't annoy you anymore. Note that this has to be repeated for every change to .net or any .net Program.  See also: Link nwp
This is a trojan horse confirmed by superantispyware. generally mscorsvw.exe is a .net file but trojan uses its name to fake it. it will suck up all your cpu resources and ultimately crash the computer or results in BSOD. it will hide itself in task manager and process explorer. check with tune up utilities, the process is showing running and using high cpu reources. search and delete the file. variz gupta
it doesn't use much CPU, but it is continuously writing to the paging file even though I have half a gig of unused RAM! Andrew/
.net framework SHOULD ONLY BE DOWNLOAD FROM OFFICIAL MICROSOFT WEBSITE other companies such as softonic will ad perameters to allow popup ads to infest Trevor Goble
Ate up CPU for about 5 mins after 17 updates. Them vanished. No computer expert, but this sounds fairly typical. Don't sweat it, let it do its thing and in less than an hr it'll be over... Jake Bullet

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Is mscorsvw.exe spyware or a virus, trojans, adware or worm? Is there a known mscorsvw.exe error?

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mscorsvw.exe [all processes]