Symptoms
- Text appears as boxes or question marks
- Font looks different from what the page intended
- Document shows a substitute font instead of the original
- Some characters render fine, others don't
Likely causes
- CommonRequired font not installed on your systemDocuments made on another computer can reference fonts you don't have.
- CommonWeb font failed to loadA website's custom font can fail to download due to a connection issue or ad blocker.
- PossibleBrowser cache serving an outdated font fileCached font data can become stale or corrupted.
- PossibleMissing language support for certain charactersNon-Latin scripts sometimes need additional language packs installed.
What to do
- Reload the page or document to see if it was a one-time loading glitch.
- Clear your browser's cache and reload the site.
- If viewing a document, check whether the required font can be installed or embedded, or ask the sender to export it as a PDF instead.
- Install any needed language pack from your operating system's settings if specific characters show as boxes.
- Disable ad blockers or content blockers temporarily, since some block font-loading resources.
- Try viewing the page or document on a different device to confirm it's a local font issue.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.