Whenever i save a drawing from visio to a PNG i get these yellow lines apearing at the edge of objects.

Dear @Mit,

Thank you for posting your question in the Microsoft Q&A forum and sharing the details and screenshots. The yellow lines you’re seeing around shapes when exporting from Visio to PNG are typically caused by anti-aliasing during image rendering, which blends edge pixels for smoothness. This blending can appear as yellow artifacts, especially with light-colored shapes on white backgrounds. 
To help me narrow down the cause, could you please provide the following details?  

1. What version of Visio are you using? 
2. Are you experiencing this issue with every drawing or just specific ones? 
3. Does the problem persist if you restart the application or your computer? 
4. Have you noticed if the lines appear in other formats, such as JPG or BMP, when you try saving in those formats instead of PNG? 

In the meantime, please try the following official troubleshooting options which usually resolve issues with basic issues: 

Option 1: Adjust PNG export settings 

• Go to File > Export > Change File Type > PNG. 
• In the Save As dialog, click Options. 
• Set Resolution to a higher DPI (e.g., 300 or 600) and disable anti-aliasing if available. 
• Ensure Transparent Background is unchecked if not needed. 

For more details, please refer to Microsoft’s official documentation: Save a Visio diagram as a graphic or image file - Microsoft Support 

Option 2: Change shape fill or border colors 

• If shapes have very light fills, consider slightly darker tones to reduce blending artifacts. 

Option 3: Export to SVG or PDF for best quality 

• If PNG is not mandatory, SVG or PDF formats preserve crisp edges without anti-aliasing issues.  

Option 4: Post-Processing option 

• If artifacts persist, crop or clean edges using an image editor (e.g., Paint.NET, Photoshop). 

Visio uses anti-aliasing to smooth edges at lower resolutions. When colors blend (e.g., white background + light fill), pixels can appear yellowish. Increasing resolution or disabling anti-aliasing minimizes this effect.  

I truly hope you understand that the initial steps I suggested may not have completely resolved the issue, as there might still be underlying causes, we haven't uncovered yet. Please know that I’m here with you every step of the way, ready to work together and do everything I can to help troubleshoot and find the best solution. 

Please let me know if you have any further questions or if the problem persists after trying these solutions. Thank you for your patience and cooperation. 

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