# Known Issues
## No OCR Support for Images
Despite some documentation suggesting OCR support, the MarkItDown library **does not perform OCR on images**. When converting image files (PNG, JPG, etc.), it only:
- Extracts EXIF metadata (if available)
- Can describe images using a multimodal LLM (if configured with an LLM client)
**Current behavior**: Screenshots and images with text will convert to empty or metadata-only Markdown files.
**Workaround**: If you need OCR functionality, you would need to:
1. Use a separate OCR tool (like `tesseract`) to extract text first
2. Or wait for OCR support to be added to the upstream MarkItDown library
## Unicode Errors with Markdown Files
Some `.md` files may fail to convert with a `UnicodeDecodeError` when they contain non-ASCII characters. This is a known limitation in the MarkItDown library's `PlainTextConverter`, which uses ASCII encoding by default.
**Workaround**: Convert these files using a different method or wait for an upstream fix in the MarkItDown library.
**Affected error**:
```
PlainTextConverter threw UnicodeDecodeError with message: 'ascii' codec can't decode byte...
```
## Office File Dependencies
Excel (.xlsx, .xls) and PowerPoint (.pptx) files require additional dependencies. If you see errors like:
```
XlsxConverter threw MissingDependencyException...
PptxConverter threw BadZipFile...
```
**Solution**: Install the required dependencies using pipx:
```bash
pipx inject markitdown-mcp openpyxl xlrd pandas tabulate
```
## Corrupted Office Files
Some Office files may fail with `BadZipFile` errors if they are corrupted or use an incompatible format. This typically happens with files that:
- Are password protected
- Use very old Office formats
- Are corrupted or partially downloaded
- Were created with non-Microsoft Office software
**Solution**: Try opening and re-saving the file in Microsoft Office or a compatible application.
## Large File Timeouts
Very large files (especially PDFs with many pages) may cause timeouts in Claude Desktop. The default timeout is 2 minutes per file.
**Solution**: For batch conversions of large files, consider:
- Converting smaller batches at a time
- Using the tool directly from command line for very large files
- Splitting large PDFs into smaller chunks before conversion
