When you use Microsoft Office 2003 to view a Web resource, you are prompted for credentials. For two weeks you are not prompted to provide credentials when you return to the Web resource. After two weeks, you are prompted for your credentials again when you try to view the Web resource.

If a Web server requires authentication to successfully complete an Office Protocol Discovery OPTIONS request, you may be prompted for credentials to complete the call. After the call is completed, the information that is gathered is cached in your registry hive so that the call does not have to be repeated again for this folder. By default, the information is cached in the registry for two weeks. After two weeks have passed, you must submit your credentials again to complete the OPTIONS call.

This problem was first fixed in a hotfix that is now contained in a service pack. If you installed the latest Office 2003 service pack, you do not have to install the hotfix.

Service pack information

This problem is corrected in Office 2003 Service Pack 3. To resolve this problem, obtain the latest service pack for Office 2003. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
After you install the service pack, follow the steps that are listed in the "How to change the registry" section of the article to set the NumWeeksToCache registry key and to activate the hotfix.

Hotfix information

To change this behavior and to extend the time that credentials are cached in the registry, apply the following hotfix and then change the registry.

How to obtain the hotfix

This issue is fixed in the Office 2003 post-Service Pack 2 Hotfix Package that is dated April 21, 2006. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

How to change the registry

Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall your operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

To extend the time that credentials are cached in the registry, change the value of the NumWeeksToCache registry key.

The value that is used in the NumWeeksToCache registry key can be any number between 1 and 520. The value 1 is the default value in which credentials are cached for two weeks. Each increment in value adds one week to the default two-week time. For example, the value 2 equals three weeks, the value 3 equals four weeks, and so on up to the maximum value of 520.

Note We recommend that you do not exceed 52 weeks unless a specific business need requires it. When a higher value is set, more space is required to keep the cache entries. Therefore, the search of all entries will be slower for the application. If you require a value more than 52 weeks, consider adjusting the MaxCount setting of the server cache so that you will not run out of room for the longer held entries. Additionally, the bigger the size of the cache, the more time may be required to perform a search of the list. This behavior may affect overall performance when you open documents by using a URL.

To change the NumWeeksToCache registry key, follow these steps:

1. Exit Office 2003.
2. Click Start, click Run, type regedit, and then click OK.
3. Locate and then click to select the following registry subkey:
   HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Common\Internet\Server Cache
4. After you select the key that is specified in step 3, point to New on the Edit menu, and then click DWORD Value.
5. Type NumWeeksToCache, and then press ENTER.
6. Right-click NumWeeksToCache, and then click Modify.
7. In the Value data box, type the value that is between 1 and 520 that you want to use, and then click OK.
8. On the File menu, click Exit to exit Registry Editor.

For more information about Office Protocol Discovery and why it was added to Office 2003, click the following article number to view the article in the Microsoft Knowledge Base:

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

This problem was first corrected in Office 2003 Service Pack 3.