How to remove an R8139n51 error
The file R8139n51.SYS is a Windows driver. A driver is a small software program that allows your computer to communicate with hardware or connected devices. This means that a driver has direct access to the internals of the OS, hardware etc.
The free file information forum can help you determine if R8139n51.SYS belonging to the Windows system or an application you can trust.
Run a free scan to check for R8139n51 drivers in need of updating
R8139n51.SYS file information
The process known as Realtek RTL8139/810x Family NDIS (version 5.1 Drv) or Realtek RTL8139/810X Family NDIS (version 5.1 Drv) or CNet FAST200 NDIS (version 5.1 Driver) belongs to software Realtek RTL8139/810x Family Fast Ethernet NIC NT Driver or Realtek RTL8139/810X Family Fast Ethernet NIC NT Driver or CNet FAST200 PCI Fast Ethernet Adapter NT Driver by Realtek Semiconductor (www.realtek.com.tw) or CNet Technology.
Description: The file R8139n51.SYS is located in the folder C:\Windows\System32\drivers.
Known file sizes on Windows 7/XP are 45,568 bytes (42% of all occurrences), 46,976 bytes or 45,312 bytes. 
The driver can be started or stopped from Services in the Control Panel or by other programs.
The program is not visible. There is no detailed description of this service. It is not a Windows core file. File R8139n51.SYS is a trustworthy file from Microsoft.
R8139n51.SYS seems to be a compressed file.
Therefore the technical security rating is 13% dangerous, however also read the users reviews.
Recommended: Identify R8139n51.SYS related errors
Important: Some malware camouflages itself as R8139n51.SYS, particularly when located in the c:\windows or c:\windows\system32 folder. Therefore, you should check the R8139n51.SYS 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.
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Mayer Benjamin
R8139n51 scanner
Security Task Manager shows all running Windows tasks including embedded hidden functions (e.g. keyboard or browser monitoring, autostart entry). A unique security risk rating indicates the likelihood of the process being potential spyware, malware, keylogger or a Trojan. Spyware Doctor detects and removes sleeping spyware, adware, trojans, keyloggers, malware and tracking threats from your hard disk. Ideal supplement to Security Task Manager. SpeedUpMyPC scans, cleans, repairs and optimizes your computer. |
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Siggi