I am on v14.2, one of my user is experiencing an "Error 500 - Internal Server Error. The server could not retrieve the document due to server-configuration or other technical problems. Contact your site administrator." when using a custom portlet. I have found a thread in the community (https://communities.ca.com/thread/241693258) and tries to reset the user's configuration by copying the url from one "good" user to the bad user's url after the action:, no success. I tried it on Chrome and IE7. I tried this because I was guessing this is caused by the filter(s) user created.
I was talking to CA Support and they suggested to re-publish the portlet, which have impact to all users so I am hesitated to re-publish.
I would appreciate if other community members have experience similar to this could share how they get it resolved.