Serialnumber of Macromedia Fireworks not accepted from Adobe

Fireworks is End of Life software since 2012.

The aged out activation server for your legacy product has probably been decommissioned.

Fireworks alternatives.
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- Illustrator CC: https://www.adobe.com/products/illustrator.html
- Photoshop Elements: https://www.adobe.com/products/photoshop-elements.html
- Photoshop CC: https://www.adobe.com/products/photoshop.html

OTHER TOOLS (raster & vector):
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- Affinity Photo & Affinity Designer: https://affinity.serif.com
- CorelDRAW Graphics Suite: https://www.coreldraw.com/
- GIMP: https://www.gimp.org/
- Gravit Designer: https://www.designer.io/en/
- Inkscape: https://inkscape.org/
- Krita: https://krita.org/
- Paint.NET: https://www.getpaint.net/
- PaintShop Pro: https://www.paintshoppro.com/
- PhotoPea: https://www.photopea.com/
- Photo Pos Pro: https://www.photopos.com/PPP3_BS/Default.aspx
- Pixlr: https://pixlr.com/
- Vctr: https://vectr.com/

Hope that helps.