REP-3000: Internal error starting Oracle Toolkit.

Issue:

Recently we had issue with Concurrent requests which having print format of PDF or XML, and excel etc. 

User reported that all reports are failing with the below error and when we did the sanity from our side we too got the same issue while opening the view log and view output of a concurrent request and error is:

"REP-3000: Internal error starting Oracle Toolkit"

 Solution:

1. Log on as root on the UNIX box.

2. Start The VNC server:
Example:
$ vncserver :0
If it's not installed on the box, have your Unix Admin's to install the VNC on the server.
3. Set the DISPLAY environment variable for Oracle Reports by performing the
following steps:
a. $ set DISPLAY=hostname:0; export DISPLAY
b. $ xhost +
c. Set the DISPLAY parameter in adcmctl.sh, adrepctl.sh,adfrmctl.sh
and gsmstart.sh to hostname:0
d. Restart concurrent manager and report server

Example to check vnc server status.

How to Verify:

1. Login with system administrator responsibility
2. Run the Active Users Concurrent Request
4. It should be completed without any issue.