dotnet/wpf · error · COMException

FILTER_E_ACCESS

FILTER_E_ACCESS

Error message

File to filter is not loaded.

What it means

COMException from XpsFilter's IFilter.GetChunk: the inner filter object is null because Init/IPersistFile::Load was never completed, so there is no loaded file to enumerate chunks from; the error is returned as FILTER_E_ACCESS with the 'file not loaded' message.

Solutions

1. Call IPersistFile.Load before GetChunk
2. Verify Load succeeded and restart the chunk loop
3. Skip the file and log when the filter cannot be loaded

Example fix

// before
var chunk = ((IFilter)filter).GetChunk();
// after
if (!loaded) ((IPersistFile)filter).Load(path, STGM.READ);
var chunk = ((IFilter)filter).GetChunk();

try { chunk = ((IFilter)filter).GetChunk(); }
catch (COMException ex) when ((uint)ex.ErrorCode == 0x80041200 || ex.ErrorCode == unchecked((int)0x80004005)) { /* skip file or reload */ }

When it happens

Trigger: Calling IFilter.GetChunk() on an XpsFilter before IPersistFile.Load has populated the inner filter.

Common situations: Indexers iterating GetChunk/GetText loops on a filter instance whose Load step failed or was skipped.

Understand the failure class

Background: "Invalid state transition" errors: "status must be X, actually Y", "already rejected/charging/uninstalled", "cannot ... while running" — what they mean when a library rejects your call — this error's family across 31 libraries.

Related errors

• E_FAIL
• E_INVALIDARG
• E_NOTIMPL
• Buffer address passed to GetText cannot be NULL.
• PrintingCanceledException

AI-assisted analysis of dotnet/wpf@81131a70a4 (2026-09-14). Data as JSON: /api/errors/0aa18d9c96fd4bae. Report an issue: GitHub.

Appendix: source

Thrown at src/Microsoft.DotNet.Wpf/src/PresentationFramework/MS/Internal/IO/Packaging/XpsFilter.cs:76

            if (cAttributes > 0 && aAttributes == null)
            {
                // Attributes count and array do not match.
                throw new COMException(SR.FilterInitInvalidAttributes,
                    (int)NativeMethods.E_INVALIDARG);
            }

            return _filter.Init(grfFlags, cAttributes, aAttributes);
        }

        /// <summary>
        /// Returns description of the next chunk.
        /// </summary>
        /// <returns>Chunk descriptor</returns>
        STAT_CHUNK IFilter.GetChunk()
        {
            if (_filter == null)
            {
                throw new COMException(SR.FileToFilterNotLoaded,
                    (int)FilterErrorCode.FILTER_E_ACCESS);
            }

            try
            {
                return _filter.GetChunk();
            }
            catch (COMException ex)
            {
                // End-of-data?  If so, release the package.
                if (ex.ErrorCode == (int)FilterErrorCode.FILTER_E_END_OF_CHUNKS)
                    ReleaseResources();

                throw;
            }
        }

        /// <summary>

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