Hi,
This error occurs in CHECK_REQUIREMENTS phase because for some reason
index 5 of table BKPF is marked for conversion in SE14.
If confirm that this object is consistent in database as well
as in ABAP dictionary then you can delete this flag, as follows:
In SE14 -> DB Requests -> Created with Import. Select the referred
entry, click on "trash" button.
Then retry the import in spam.
Regards, Premsukh