Dealing with Wpcap.dll Not Found Error Messages

What is wpcap.dll?

Wpcap.dll is a file which is part of WinPcap software designed by CACE technologies, now owned by Riverbed Technologies. This is a specialized network administration software designed for Windows X86 and X64 systems.

What are the errors generated by wpcap.dll?

The errors are generated because of the corrupt wpcap.dll files, and the errors displayed on the screen are:

  • 'Wpcap.dll Not Found'
  • 'Cannot start [APPLICATION]. A required component is missing: wpcap.dll. Please install [APPLICATION] again.'
  • 'This application failed to start because wpcap.dll was not found. Re-installing the application may fix this problem.'
  • 'Cannot find [PATH]\wpcap.dll'
  • 'The file wpcap.dll is missing.'

What are the operating systems affected because of wpcap.dll corruption?

This is a custom designed network administration software for Windows, so the operating systems affected are:

  • Windows NT
  • Windows 2000
  • Windows XP
  • Windows 2003

This software is also compatible with Windows 95, 98, and ME, but these are not supported now. The WinPCap software is still not tested on Windows Vista & 7, but wpcap.dll errors can generate errors with WinPcap.

How to fix errors generated by wpcap.dll

WinPcap is a tool specifically designed for Windows based systems to transmit captured network packets. This software is helpful in bypassing the protocol stack and also helps in kernel level packet filtering. When the core wpcap.dll file of this software is corrupted, the system starts giving errors. To fix these errors, follow these methods:

1) Using System Restore
2) Uninstalling and Reinstalling the WinPcap software
3) Registering the Wpcap.dll file

Using System Restore

Note: This method works on Windows XP, Vista, and 7 only. If you are using Windows NT, 2000 or 2003, you can skip this method.

  1. Click on Start and then click on All Programs
  2. Go to Accessories and choose System Tools
  3. Click on the System Restore option
  4. From the list of dates provided, choose a date before the occurrence of the wpcap.dll error
  5. Click Next to apply the settings of the date chosen from the list and restart the system

This will overwrite the present registry with that of the date chosen. This should solve the issue with the wpcap.dll file. You can follow the next method if the error still pops up.

Uninstalling and Reinstalling WinPcap

  1. Click on Start and go to settings
  2. Choose Control Panel
  3. Choose Add or Remove Programs in XP, 2000 & 2003/ Program and Features in Win 7, Vista
  4. From the list, choose WinPcap software and then click on Uninstall

After you uninstall the program, it is better to restart the OS as this software affects the core files of the OS. Now, you have to download the latest version of WinPcap and then install it. If you get an error related to wpcap.dll even after reinstalling a newer version, try the next method.

Registering the Wpcap.dll file

Make sure you are logged in as the administrator and then follow these steps:

  1. Click on Start and then Run
  2. In the dialog box, type cmd and click OK
  3. Now type regsvr32 wpcap.dll and press Enter

This should completely solve the issue with wpcap.dll files.