Troubleshooting and resolving Web proxy event ID 127 (244223)

MORE INFORMATION

The common causes of this error message and the appropriate resolutions are listed below.

Incorrect Web proxy cache paths

The Web proxy cache paths may be incorrect. Confirm and correct the registry paths if necessary, so that the CachePath values in the following registry location match the actual path to the Urlcache folder: For each Pathx you can find CachePath values. For example, if the Urlcache folder is located in C:\Urlcache, the CachePath value for Pathx is C:\Urlcache\Dirx.

The Web proxy DLL filter is not loaded

If the Web proxy DLL filter is not loaded, it is either not present or a red arrow that points down is displayed next to it. To confirm the configuration or to correct issues with the Web proxy filter, use the following steps:

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.

Incorrect permissions on the W3proxy.dll file

The permissions on the W3proxy.dll file may be incorrect.

The W3proxy.dll file is located in the %SystemRoot%\Inetpub\Scripts \Proxy folder, or wherever the Inetpub directory is located (usually in the root of the drive where IIS was installed)..

The NTFS File System (NTFS) Permissions should be:

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

Incorrect permissions on the Urlcache folder

The permissions on the Urlcache folder may be incorrect. Ensure that the NTFS file system permissions include the following permissions:

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

Incorrect local address table (LAT) entries

By default, the LAT include the Private IP ranges:

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

The LAT should include entries from the NT Internal Routing Table. For example, if the Network Interface Card (NIC) connected to the Local Area Network (LAN) has an Internet Protocol (IP) of 10.0.0.1 with a subnet mask of 255.255.255.0, the LAT should have the following entries added:

FromTo
   10.0.0.0 - 10.0.0.255

To confirm or add the NT Internal Routing Table to the LAT use the following steps:

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.

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

If WINS is bound to the external interface, use the following steps to unbind WINS:

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.

WINS server entries for the external interface

The external interface may have entries for the WINS server. To remove the WINS server addresses 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.

Internet Explorer is not bypassing proxy for local addresses

If you are seeing the "Source Text For Default Internet Web Site" when trying to access external Internet web sites, in addition to getting the above error, then Internet Explorer may not be configured to bypass Proxy for local addresses. This setting should be configured on the server itself.