Yes, I am using EnsLib.FTP.InboundAdapter.

Error doesn't say much "ERROR <Ens>ErrGeneral: Failed to delete 'testfile.dat'
from FTP server after successful processing - :"

We would want the Business Service to delete the file, which it can do just fine if the file is smaller.  I have tried a file in the KB; file is deleted no error.  Same process tried a file 34 megs and the delete error happens.  It seems like it might be trying to delete the file before the Business Service or Business operation has finished processing the messages so it see the file as being is use.  If so that is true, is there a way to slow down the delete process to give time for the give time for processing to finish.