EBS升级到R12.2.4后，进入系统操作老是报以下错误：
通过谷歌发现有人遇到相同的问题，并提供了解决方案。
原文地址：http://onlineappsdbaoracle.blogspot.com/2016/05/afterebs-12.html
This error is because the forms_server was missing in the Datasources target.
Follow the below steps to resolve the issue:
Login to the weblogic console
1) Click on “Lock and Edit”
2) Navigate to Domain structure --> Services -->Data sources
Here in the EBSDataSource targets, you should see both oacore_cluster1 and forms_cluster1.
forms_cluster1 was missing in the targets. Add it to the EBSdatasource target list
3) Click on the EBSDatasource and then go to the Targets section.
In this page, check the box for forms_cluster1.
1) Save and activate the changes.
After the changes, EBSDatasource target will be as below:
