can someone help me with some details explanation for using the export cdt to ex

In the UI doen't give me any error, if I look at the alerts the message is:
Problem: An error occurred in executing an Activity Class.
Recommended Action: Examine the activity class to correct the error and then resume.
Priority of this problem: High Priority

I found in the log's something like this: [9/14/15 9:09:02:655 GMT+02:00] 000002d4 SystemOut O 2015-09-14 09:09:02,655 [WebContainer : 7] ERROR com.appiancorp.analytics.excel_export.ExportCdtToExcel - The input fields does not match the fields in the CDT
Probably you are right.
What I do in my process:
1. I habe a script task that get's the cdt data in a process variable.
2. I configure export and ad as a cdt the process variable.

For what I saw in the process variable the array is ok.
Can you explain to me, what I should do?

In the UI doen't give me any error, if I look at the alerts the message is:
Problem: An error occurred in executing an Activity Class.
Recommended Action: Examine the activity class to correct the error and then resume.
Priority of this problem: High Priority

I found in the log's something like this: [9/14/15 9:09:02:655 GMT+02:00] 000002d4 SystemOut O 2015-09-14 09:09:02,655 [WebContainer : 7] ERROR com.appiancorp.analytics.excel_export.ExportCdtToExcel - The input fields does not match the fields in the CDT
Probably you are right.
What I do in my process:
1. I habe a script task that get's the cdt data in a process variable.
2. I configure export and ad as a cdt the process variable.

For what I saw in the process variable the array is ok.
Can you explain to me, what I should do?