Troubleshooting and resolving Web proxy event ID 127

Back to the top

Incorrect Web proxy cache paths

Back to the top

The Web proxy DLL filter is not loaded

1. Confirm that the W3proxy.dll file is located in the %SystemRoot%\Inetpub\Scripts\Proxy folder, or wherever the Inetpub directory is located (probably in the root of the drive where IIS was installed).
2. Open the Microsoft Management Console (MMC).
3. Right-click the default Web site, and then click Properties.
4. Click the ISAPI Filters tab. If a red arrow that points down is displayed next to the W3proxy.dll file, use the following steps:
   1. Click the W3proxy filter, and then click Remove.
   2. Click Add, and then type w3proxy for the file name.
   3. Click Browse, and then click the W3proxy.dll file in the %SystemRoot%\Inetpub\Scripts\Proxy folder, or wherever the Inetpub directory is located (in the root of the drive where IIS was installed).
   4. Click OK to add the filter.
   5. Click OK, and then quit and restart the Default Web Site
5. Restart the server.

Back to the top

Incorrect permissions on the W3proxy.dll file

   Administrators     Full Control
   Everyone           Full Control
   Server Operators   Change
   System             Full Control
   W3proxy.dll        Execute
				

Back to the top

Incorrect permissions on the Urlcache folder

   Administrators     Full Control
   Creator/Owner      Full Control
   Domain Admins      Full Control
   Domain Users       Read
   Server Operators   Change
   System             Full Control
				

Back to the top

Incorrect local address table (LAT) entries

FromTo
   10.0.0.0 - 10.255.255.255
   172.16.0.0 - 172.31.255.255
   192.168.0.0 - 192.168.255.255

FromTo
   10.0.0.0 - 10.0.0.255

1. Open the Microsoft Management Console (MMC).
2. Right-click Web Proxy, and then click Properties.
3. Under the Service Tab, click the Local Address Table button.
4. Click the Contruct Table button.
5. Select the Load from NT Internal Routing Table checkbox.
6. Select the option button that indicates Load known address ranges from the following IP interface cards.
7. Select the checkbox next to the NIC that corresponds with the internal network.
8. Select the checkbox Add the private ranges 10.x.x.x, 192.168.x.x, and 172.16.x.x - 172.31.x.x to the table (if you would like the private IP ranges in the LAT).
9. Click OK.
10. Click OK to the pop-up Setup Message.
11. Click OK, then click Apply, and then click OK.
12. Then quit and start the Web Proxy, Winsock Proxy, and Socks Proxy services.

Back to the top

Windows Internet naming service (WINS) may be bound to the external interface

Windows NT 4.0

1. Click Start, point to Settings, click Control Panel, and then double-click Networks.
2. On the Bindings tab, click All Protocols from the list.
3. Expand WINS client (TCPIP).
4. Click the external interface (for example, the network card name or all Remote Access Service WAN adapters).
5. Click Disable for Each instances of WINS for each external interface, and then click OK.
6. Click OK and then restart the server.

Windows 2000

1. Click Start, point to Settings, click Control Panel, and then double-click Network and Dialup Connections.
2. Click on the external network card, right-click and select Properties.
3. Select Internet Protocol (TCP/IP), and click Properties.
4. Click Advanced, and then select the WINS tab.
5. Click the radio button for Disable NetBIOS over TCP/IP.

Back to the top

WINS server entries for the external interface

1. Click Start, point to Settings, click Control Panel, and then double-click Networks.
2. On the Protocols tab, click TCPIP, and then click Properties.
3. On the WINS address tab, click your external network adapter in the list.
4. Delete the entries from the Primary and Secondary WINS server boxes.
5. Click OK, and then click OK again.
6. Restart the server.

Back to the top

Internet Explorer is not bypassing proxy for local addresses

Back to the top