After an upgrade, the customer-developed Syncplicity clients are can no longer upload files to Syncplicity cloud or on-prem Storage Connectors. For example, this could occur when performing multipart post requests to the following Storage Connector endpoints:
The multipart upload request performed by the customer-developed Syncplicity client does not conform with RFC 1341 - 7_2_Multipart. The Upload API of Storage Connector 3.2 enforces that RFC. Storage Connector 2.x was not strict about the multipart upload requests.
To resolve this issue, the customer-developed Syncplicity clients must modify their multipart upload requests to be compliant with RFC 1341. The most frequent issue is with the end of the POST request: last boundary should end with --, followed by two new lines (CRLF CRLF):