Most antivirus programs identify msys1.dll as malware—for example Sophos identifies it as Mal/Generic-S, and Avast identifies it as Win32:Dropper-gen [Drp].
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GNU does not provide any particulars about the software with which the process was installed, nor is the developer identified within the file.
Description: Msys1.dll is not essential for Windows and will often cause problems. Msys1.dll is located in a subfolder of "C:\Program Files (x86)"—primarily C:\Program Files (x86)\GNU\.
The file size on Windows 10/8/7/XP is 18,944 bytes.
A .dll file (Dynamic Link Library) is a special type of Windows program containing functions that other programs can call. This .dll file can be injected to all running processes and can change or manipulate their behavior. There is no information about the author of the file. The software starts upon Windows startup (see Registry key: AppInit_DLLs). It is not a Windows core file. Msys1.dll is able to monitor applications. Therefore the technical security rating is 68% dangerous.
Recommended: Identify msys1.dll related errors
If msys1.dll is located in the C:\Windows\System32 folder, the security rating is 100% dangerous. The file size is 18,944 bytes. There is no file information. It can change the behavior of other programs or manipulate other programs. The program is not visible. There is no detailed description of this service. The software is loaded during the Windows boot process (see Registry key: AppInit_DLLs). It is not a Windows system file. Msys1.dll is able to monitor applications.
Important: You should check the msys1.dll process on your PC to see if it is a threat. We recommend Security Task Manager for verifying your computer's security. This was one of the Top Download Picks of The Washington Post and PC World.
The following programs have also been shown useful for a deeper analysis: ASecurity Task Manager examines the active msys1 process on your computer and clearly tells you what it is doing. Malwarebytes' well-known Banti-malware tool tells you if the msys1.dll on your computer displays annoying ads, slowing it down. This type of unwanted adware program is not considered by some antivirus software to be a virus and is therefore not marked for cleanup.
A clean and tidy computer is the key requirement for avoiding PC trouble. This means running a scan for malware, cleaning your hard drive using 1cleanmgr and 2sfc /scannow, 3uninstalling programs that you no longer need, checking for Autostart programs (using 4msconfig) and enabling Windows' 5Automatic Update. Always remember to perform periodic backups, or at least to set restore points.
Should you experience an actual problem, try to recall the last thing you did, or the last thing you installed before the problem appeared for the first time. Use the 6resmon command to identify the processes that are causing your problem. Even for serious problems, rather than reinstalling Windows, you are better off repairing of your installation or, for Windows 8 and later versions, executing the 7DISM.exe /Online /Cleanup-image /Restorehealth command. This allows you to repair the operating system without losing data.