Oracle Apps R12 Forms Not Opening

The forms for Oracle Apps EBS may not open for many reasons. Follow below steps to find out:-

For a particular Form:-

1. It displays some message which can help you finding out the cause.
2. Most of the time its related to some database objects or the particular form executable.
   a. Compile all ( Mainly Apps owned ) db objects.
   b. Compile particular form executable.

For All forms:-

1. Always check the DB, and alert log.
2. Check file system space.
3. Check Apache and Forms log. $LOG_HOME/10.1.3/Apache/Apache/logs and $LOG_HOME/10.1.2/forms/logs
4. If you are using R12 with IE8 then check Metalink doc 1069497.1, for Cross Site Scripting(XSS) settings (make it to relevant tab of your internet options). Also check 389422.1 for recommended browsers and settings.
5. Check timestamp for files like $AU_TOP/resource/CUSTOM.* , this will tell you if someone has modified the pll and then the changes should be reverted back.
6. Try checking the form sessions from your server as below
   ps -ef | grep frm
   This will show the frmsrv and frmweb processes. If it doesn't then the issue is in spawning form session.
   You can check the timestamp for frmsrv/frmweb executable, if this has got changed. You can relink this by below.
   a. Source the Application environment
   b. from location $ORACLE_HOME/forms/lib
   run :- make -f ins_forms.mk install
7. In other case if from sessions are there and you are not able to open the form, then check the direct form login as below.
   http://server:port/forms/frmservlet - for servlet mode
   http://server:port/OA_HTML/frmservlet - for socket mode
8. If above works then you can go to adadmin and compile jsps, or can have clear cache bounce.
9. If step 6 doesn't work then check for dbc file present at $FND_SECURE.
   a. The file should have correct entries for Application Server Id, as it is in FND_NODES table.
   b. All the passwords guest,applsyspub etc are ok, or change the guest password using FNDCPASS
   c. You can correct the dbc file manually, or regenerate using  $COMMON_TOP/admin/install/adgendbc.sh
10. Bounce forms server and retry.