dotnet/wpf · warning · COMException

0x80041705

0x80041705

Error message

GetText operation is not supported on current chunk.

What it means

In the IFilter protocol, a chunk carries either text or property values, never both. PackageFilter.GetText only works while the current chunk is a content (text) chunk (Progress.FilteringContent); otherwise it throws FILTER_E_NO_TEXT (0x80041705) as a COMException, indicating GetText is not valid for the chunk you are on.

Solutions

1. Only call GetText when the current chunk represents text content; check the chunk attributes (CHUNKSTATE) returned by GetChunk before calling.
2. Call GetValue() instead when the chunk is a core-properties chunk.
3. Catch COMException with HResult 0x80041705 and skip text extraction for that chunk, continuing with the next.

Example fix

// before
filter.GetChunk(out chunk);
filter.GetText(ref bufCount, pBuffer); // throws on property chunks
// after
filter.GetChunk(out chunk);
if (chunk.flags == CHUNKSTATE.CHUNK_TEXT)
    filter.GetText(ref bufCount, pBuffer);
else
    IntPtr v = filter.GetValue(); // property chunk

// After GetChunk, only call GetText for content (text) chunks:
bool canGetText = (chunk.flags & CHUNKSTATE.CHUNK_TEXT) != 0;

static bool IsTextChunk(System.Runtime.InteropServices.ComTypes.STAT_CHUNK c)
    => (c.flags & System.Runtime.InteropServices.ComTypes.CHUNKSTATE.CHUNK_TEXT) != 0;

try { filter.GetText(ref bufCount, pBuffer); }
catch (COMException e) when (e.HResult == unchecked((int)0x80041705))
{ /* FILTER_E_NO_TEXT: current chunk has no text — skip or call GetValue */ }

When it happens

Trigger: Calling GetText while the current chunk is a core-properties chunk (or before any chunk has been fetched / after chunks are exhausted), i.e. whenever _progress != Progress.FilteringContent.

Common situations: Indexers that call GetText unconditionally on every chunk instead of checking the chunk's attributes/flags; core-property chunks carry values, so GetText fails on them.

Understand the failure class

Background: UnsupportedOperationException and "is not supported" errors: when a library deliberately refuses a call — this error's family across 30 libraries.

Related errors

• 0x80041706
• 0x80041700
• 0x80041702
• 0x80041705
• 0x80041705

AI-assisted analysis of dotnet/wpf@81131a70a4 (2026-09-14). Data as JSON: /api/errors/d58dff7b87507c5c. Report an issue: GitHub.

Appendix: source

Thrown at src/Microsoft.DotNet.Wpf/src/PresentationFramework/MS/Internal/IO/Packaging/PackageFilter.cs:226

                    //
                    // No more filters. Filtering completed.
                    // Throw FILTER_E_END_OF_CHUNKS exception.
                    //

                    throw new COMException(SR.FilterEndOfChunks,
                        (int)FilterErrorCode.FILTER_E_END_OF_CHUNKS);
                }
            } 
        }

        /// <summary>
        /// Gets text content corresponding to current chunk.
        /// </summary>
        public void GetText(ref uint bufferCharacterCount, IntPtr pBuffer)
        {
            if (_progress != Progress.FilteringContent)
            {
                throw new COMException(SR.FilterGetTextNotSupported, 
                    (int)FilterErrorCode.FILTER_E_NO_TEXT);
            }

            _currentFilter.GetText(ref bufferCharacterCount, pBuffer);
        }

        /// <summary>
        /// Gets the property value corresponding to current chunk.
        /// </summary>
        /// <returns>Property value</returns>
        public IntPtr GetValue()
        {
            if (_progress != Progress.FilteringCoreProperties)
            {
                throw new COMException(SR.FilterGetValueNotSupported,
                    (int)FilterErrorCode.FILTER_E_NO_VALUES);
            }

View on GitHub (pinned to 81131a70a4)