When installing Netmon service on a Windows 7 PC you recieve the error:
“filters currently installed on the system have reached the limit”

Windows 7 has a default limit set to 8. You are able to manually increase this limit to 14:

To resolve this problem, you will need to adjust the value of HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Network\

  1. Click Start , click Run , type regedit , and then click OK .
  2. Locate and then click the following registry subkey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Network\
  3. In the right pane, right-click MaxNumFilters, and then click Modify
  4. Change the value to “14”, and click to select the Decimal option, and then click OK.
  5. Close the Registry Editor

If this value is already set to 14 you may need to uninstall some of the other network filter drivers.

No reboot required.