A few things could cause this problem:
(a) You are trying to automatically encode/decode an open type but forgot to set the AUTOMATIC_ENCDEC flag by calling ossSetFlags() or ossSetEncodingFlags(). (See section 4.3.21 in the April 2011 OSS ASN.1/C API Reference Manual for more about the AUTOMATIC_ENCDEC flag.)
(b) You are trying to automatically encode/decode an ASN1.DeferDecoding open type value. Open types created by the use of the ASN1.DeferDecoding directive can only be manually encoded/decoded separately from their containing structures.
(c) You are trying to automatically encode/decode an open type which has no component relation constraint applied to it in the ASN.1 specification. Only open types with component relation constraints may be encoded/decoded automatically.
(d) You are manually encoding/decoding an open type but forgot to set the encoded and length fields of the OpenType instance to point to the manually encoded PDU and its length.
The samples included with some of the Knowledge Center answers are meant for your general understanding of the OSS products. Different versions of the products might produce slightly different outputs. Consult the products documentation and samples for the most up-to-date products information and code examples.
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