NotebookLM is useful for reading, summarizing, and asking questions about your own materials. But sometimes, when you try to add a PDF, audio file, MP3, TXT file, YouTube link, or web page, you may see the message "Error uploading source" or "Error uploading source. Try again."
This guide shares 7 proven fixes for the NotebookLM "Error uploading source" issue . While resolving the upload problem, you can use Diagrimo, a reliable diagram maker , to turn notes into diagrams, mind maps, or flowcharts for instant organization.
Why Won't My Sources Upload to NotebookLM?
The message "NotebookLM error uploading source" means NotebookLM failed to import or process the material you tried to add to your notebook. In NotebookLM, a "source" refers to any document, file, link, or other content you upload or import into a notebook.
Several common issues can prevent a source from uploading successfully. Most problems stem from unsupported formats, file size limits, text or transcript readability issues, or temporary browser and network glitches.
Common reasons include:
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The file type is not supported by NotebookLM.
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The file is larger than the upload limit.
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The source contains too many words.
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The notebook has reached the source limit.
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The PDF is scanned, encrypted, damaged, or not text-based.
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The audio or MP3 file has unclear speech or no speech.
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The YouTube video has no available transcript.
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The web page is behind a login, paywall, or dynamic script.
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NotebookLM is stuck loading because of browser cache, extensions, or network issues.
With these causes in mind, you can use the step-by-step fixes below to resolve the "NotebookLM error uploading source" issue.
How to Fix NotebookLM Error Uploading Source: General Fixes
Use these general fixes first. They work for most NotebookLM upload errors, no matter whether you are adding a PDF, audio file, TXT file, YouTube link, or web source.
Check NotebookLM Source Limits
NotebookLM may fail to upload a source if it exceeds the official limits. A notebook can contain up to 50 sources . Each source can contain up to 500,000 words , and uploaded files can be up to 200 MB .
If your source is too large, split it into smaller parts, remove unnecessary pages, or create a separate notebook for another topic.
Make Sure the Source Type Is Supported
NotebookLM supports many common source types, including PDF, TXT, Markdown, CSV, DOCX, PPTX, audio files, web URLs, YouTube URLs, Google Docs, Google Slides, Google Sheets, images, and ePub files.
If your source type is not supported, convert it to a simpler format such as PDF, TXT, DOCX, MP3, or WAV.
Re-export or Convert the Source
If the file looks normal but still fails, it may be damaged, restricted, or poorly formatted. Re-export the file from the original app, or convert it to another supported format.
For example:
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Export a PDF again from the original document.
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Convert a PDF to DOCX or TXT.
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Convert a DOCX file to PDF.
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Save a web article as a clean PDF.
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Convert audio to MP3 or WAV.
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Copy and paste the text directly into NotebookLM.
This is one of the most effective fixes when the file opens normally on your computer but still fails in NotebookLM.
Try a Clean Upload Environment
Browser or network issues can also cause "Error uploading source. Try again" in NotebookLM. Try refreshing the page, clearing cache, disabling extensions, using incognito mode, switching browsers, or uploading with a stable connection.
If a small TXT file uploads successfully, the issue is more likely related to your original source.
Split or Simplify the Source
Large or complex sources are more likely to fail. If possible, remove unnecessary images, blank pages, appendices, repeated text, or unrelated sections.
You can also upload a short sample first. If the sample works, split the original source into smaller topic-based files.
How to Fix NotebookLM Error Uploading Source by File Type
After trying the general fixes, check the file-specific causes below. This section focuses only on problems that are common to each source type.
Fix NotebookLM Error Uploading Source PDF
PDF upload errors often happen when NotebookLM cannot read the document text . Open the PDF and try selecting a sentence. If the text cannot be selected, the file may be a scanned PDF.
Use OCR to convert scanned pages into readable text, then upload the new PDF. If the PDF is password-protected , remove the protection first. If NotebookLM misses pages or only imports part of the document, split the PDF into smaller sections and upload them separately.
Fix NotebookLM Error Uploading Source TXT
TXT upload errors are usually related to encoding or messy content. If your TXT file shows strange characters, save it again with UTF-8 encoding.
Also check whether the file is empty, full of symbols, or made mostly of logs, code, or repeated text. Clean the content before uploading. If the file is very long, divide it into smaller sections or paste the text directly into NotebookLM.
Fix NotebookLM Error Uploading Source Audio
Audio source errors usually happen when NotebookLM cannot transcribe the file clearly . Make sure the recording contains speech, not only music, silence, or background noise.
If the audio is unclear, clean the recording, increase the volume, or upload a shorter clip first. For long interviews, lectures, or meetings, split the audio into smaller parts before uploading.
Fix NotebookLM YouTube Source Is Empty
NotebookLM imports YouTube videos through transcripts , not the video itself. If the YouTube source is empty, the video may not have captions or an available transcript.
Make sure the video is public and has captions. If the video was uploaded recently, wait and try again later. If NotebookLM still cannot import it, copy the transcript manually and paste it as a text source.
Fix NotebookLM Error Uploading Source MP3
MP3 is a supported audio format, but some MP3 files may still fail because of unusual encoding or file damage .
Try re-exporting the MP3 with standard settings, or convert it to WAV and upload again. If the MP3 is very long, trim silence and split it into shorter files. If a short sample uploads successfully, the original MP3 may be too long or difficult to process.
Fix NotebookLM Web Source Upload Error
Web source errors usually happen when NotebookLM cannot access the page text . This is common with pages behind login screens, paywalls, dynamic scripts, or pages that mainly contain images or embedded media.
Use the direct article URL instead of a homepage or search page. If the URL still fails, copy the main text into NotebookLM or save the page as a clean PDF and upload it instead.
A Faster Way to Organize Source Content: Try Diagrimo
If NotebookLM keeps showing "Error uploading source. Try again", you may not want to wait until the file finally uploads. In that case, you can use another tool to organize the key information first.
Diagrimo is an AI text-to-visual tool that can turn plain text into structured visuals, such as diagrams, flowcharts, mind maps, timelines, SWOT charts, and infographics. Instead of uploading a source and waiting for NotebookLM to process it, you can paste your notes, article text, meeting content, or study material into Diagrimo and quickly turn it into a visual format.
This can be useful when:
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You need to summarize a long text visually.
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You want to turn study notes into a mind map.
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You need a flowchart for a report or presentation.
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NotebookLM is not loading sources, but you still need to organize the content.
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You want a quick visual overview before uploading the source again.
Conclusion
NotebookLM error uploading source is usually caused by unsupported files, source limits, unreadable PDFs, unclear audio, unavailable YouTube transcripts, inaccessible web pages, or browser and network issues. Start with the general fixes first, then use the file-specific solutions for PDF, audio, MP3, TXT, YouTube, or web sources.
If NotebookLM still does not upload your source and you need to keep working, Diagrimo can help you turn key text into visual diagrams, mind maps, or flowcharts while you wait or troubleshoot, so you can understand the information faster.
- AI text-to-visuals turns ideas into diagrams or infographics.
- Customizable styles match your brand and presentation tone.
- Share anytime by exporting in various formats and a link.
- No design skills needed for presentations, teaching, or reports.
FAQs
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How Do I Upload Sources to NotebookLM?
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How Do I Upload More Files to NotebookLM?
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How Do I Fix Error Uploading File on NotebookLM?
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Why Does Uploading a File Fail in NotebookLM?
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What Is the NotebookLM Source Limit?
Open a notebook in NotebookLM, then choose a supported source type such as a PDF, TXT file, Google Doc, web URL, YouTube URL, or audio file. Upload or paste the source, then wait for NotebookLM to process it.
If you reach the source limit, create a new notebook, remove unused sources, or combine related files into one document. You can also split a large project into multiple notebooks to keep each notebook easier to manage.
Check whether the file type is supported, make sure the file is under the size and word limits, rename the file, re-export it, and try another browser. If it is a PDF, make sure the text is selectable.
Uploading may fail because the file is unsupported, too large, damaged, encrypted, unreadable, or blocked by browser/network issues. For YouTube and web sources, the content must also be publicly accessible and readable by NotebookLM.
NotebookLM allows up to 50 sources per notebook. Each source can contain up to 500,000 words, and uploaded files can be up to 200 MB . If you reach the NotebookLM source limit, create another notebook, remove unnecessary sources, or combine smaller related files into one source. For very large documents, split the content into smaller sections so NotebookLM can process them more reliably.
