is the user-mode portion of the Win32 subsystem (Win32.sys is the kernel-mode portion) and the main executable for the Microsoft Client/Server Runtime Server Subsystem. It is responsible for managing most graphical commands in Windows, console windows, creating and/or deleting threads, and some parts of the 16-bit virtual MS-DOS environment. This process is important for stable and secure operation of your system and should not be terminated. Determining whether csrss.exe is malware or a legitimate Windows process usually depends on the location
(path) it is running from. One of the ways that malware tries to hide is to give itself the same name as a legitimate or critical system file. However, it then places itself in a different location (folder) than where the legitimate file resides and runs from there. The legitimate csrss.exe file is located in the C:\Windows\System32 folder but you may find legitimate copies in other folders such as:
If found running from a different location, it's usually indicative of malware.
Most of the processes in Windows Task Manager
will be legitimate but it does not provide enough information. These are tools to investigate running processes, services and gather additional information to identify them or resolve problems:
These tools will provide information about each process, CPU usage, file description and its path location
. Most of them are stand-alone apps in a zip file so no installation is necessary.
-- System Explorer
provides a security check
of running processing using their online security database when you first launch the program. Just press the Security Scan
tab at the top, then click Start Security Check
. After the check you can click the link to See the results of the security check >>
. Keep in mind, that the check is not a guarantee of what is or is not detected as malware.
-- Process Explorer
shows two panes by default: the upper pane
is always a process list and the bottom pane
either shows the list of DLLs loaded into the process selected in the upper pane, or the list of operating system resource handles (files, Registry keys, synchronization objects) the process has open. In the menu at the top select View > Lower Pane View to change between DLLs and Handles.
Anytime you come across a suspicious file or one that you do not recognize, search the name using Google <- click here for an example
: When looking at the search results, be aware many sites may provide bogus information about a file name and claim it is malware or related to a registry error in order to get you to download or buy a program to fix it.
Or search the following databases:
If you cannot find any information, the file has a legitimate name but is not located where it is supposed to be, or you want a second opinion, submit it to one of the following online services that analyzes suspicious files:
In the "File to Scan
" (Upload or Submit) box, browse to the location of the suspicious file(s) and submit (upload) it for scanning/analysis. If you get a message saying "File has already been analyzed
", click Reanalyze
or Scan again