Error: 501 Not Implemented:

1.  Getting frequent error 501 not implemented on the browser with IE7 and IE8.

2.  Component page reset. Users are getting kicked out to first page or the search dialog box in the middle of a multi page transaction and losing the data they have entered.

3.  Suddenly the page will become unresponsive and entire browser will freeze and will require restart of the browser.

All the 3 symptoms were annoying for the users and we eventually traced it to AJAX feature, that results in loss of POST data.

Turning off the AJAX setting resolved all 3 issues. Here is a way to turn off the AJAX

Go to PeopleTools –> Web Profile > Open the Web profile you use for e.g. DEV or PROD.

Go to Custom Properties and Add a Property AJAX of type Boolean and set its value to false. This will turn off the AJAX. To enable it again make it true or remove the row. Bounce all the Web servers using this web profile to make this setting take effect.

Though the above changes resolves the issue, this is not desirable and also may not be supported in future peopletools release. I have found this issue to be related to a bug in IE7 and IE8 when used with Windows XP OS. Fortunately microsoft includes the hotfix to resolve the issue, however registry change needs to be made to enable the hotfix. For more details, see this following KB :http://support.microsoft.com/kb/895954 - When you use Microsoft Internet Explorer or another ! program to perform a re-POST operation, only the header data is posted. See How to enable this hotfix section for registry changes.

Basically, the issue happens as IE sends the AJAX request in 2 tcp ip packets one for the header and one for the body. When network error happens, and ie tries to send the ajax request again, it fails to send the body. This causes PIA to loose the session state and we see the issues described above. The other browsers Firefox, Safari and Chrome do not send ajax request in multiple packets and this issue does not appear there.

Also see this article on further clarification on which registry key needs to be modified : http://www.geoffchappell.com/viewer.htm?doc=notes/windows/ie/featurecontrol.htm

According to this , you can specify the value in any one of the following location, in order of decreasing precedence.

HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Internet Explorer\Main\FeatureControl

HKEY_CURRENT_USER\Software\Policies\Microsoft\Internet Explorer\Main\FeatureControl

HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main\FeatureControl

HKEY_LOCAL_MACHINE\Software\Microsoft\Internet Explorer\Main\FeatureControl

Please leave comments, if applying the above registry changes resolves the issue.

PeopleSoft has also published this resolution on My Oracle Support (MOS) - E-PIA: PeopleTools 8.50 and 8.51 - Intermittent "Error 501--Not implemented" Messages when Navigating to a Page Using IE7 or IE8 Browser. Doc ID : 1337266.1