Automation error, the remote procedure call failed

Hi.

I have created a tool that does the following using the OLE Automation interface.

(1)Divide the pdf file page by page(PDDoc.GetJSObject.extractPages)
(2)The divided pdf file's name is from the contents of each page(PDDoc.GetJSObject.getPageNumWords)
(3)Get the contents from each divided pdf file(about 250 divided files) and

　　check if the file name match(PDDoc.GetJSObject.getPageNumWords).

When getting the contents of each file in (3), run-time error '-2147023170(800706be)' occurs,
that says automation error, the remote procedure call failed.
When the error occured, acrobat application was terminated even though there was no process to terminate the application.
The error does not occur in the DC version, but in other versions(XI, 9)

What can I do to solve this? Please give me some advice.