Adding Attachments in Oracle EBS 12.2.6

In Oracle EBS 12.2.6, we are unable to upload any attachments with the "Attachment Type = File" to iProcurement, Purchasing or iSupplier Portal.  When an attempt is made to upload an attachment of the type File, the following error is triggered:

Form validation failures:  The file does not exist or is an empty file.  Has any one else come across this issue?  We will not be able to go live unless we are able to upload file attachments to purchasing and invoice documents.

    

Thanks in advance!

https://qa-oracleapps.humana.com/OA_HTML/OA.jsp?page=/oracle/apps/icx/por/req/webui/EditSubmitPG&porMode=display&_ti=1439886867&retainAM=Y&addBreadCrumb=N&OASF=ICX_POR_EDIT_REQ&OAHP=null&PersonalizationParam=PersonalizationParamAdmin&oapc=40&oas=mLtpaEzE9unQYBSvXng7Ag..