Failed to install the web control with prompt "NPF installation failed"

Question

I tried to install the web control, but failed and received an error message "NPF installation failed". Why?

Reason

This might caused by the following two reasons:

• The previous web controls have not been uninstalled completely.

• Other programs in the system occupied NPF.

Solution

• Make sure that the web controls that were previously installed are uninstalled completely.

• Quit NPF tools which use SADP (such as Wireshark, SADP, iVMS-4200, etc.). Then restart the computer.