Precal server error when calling workbook

Hello SDN,

I have developed a program which is used for sending Email to our users via precalculate server, and everything works well except the following one.

When I execute the program, both in the client and in background, a dialog will be raised which ask me to enter the <b>user name</b> and <b>password</b> to logon the BW server, and it only happens when the program calls workbook.

If I input user name and password, then an error "<b>Failed to pass connection data to rfc</b>" is raised and the program will stop at that point.

but if I click<b> cancel</b> on the dialog, everything goes well...I mean the user will receive the Email and the attach file(Excel) can be opened.

Could you help resolve the issue? I do not want the dialog to be raised.