Have you ever tried to upload a creative to Google Ad Manager only to be presented with this unhelpful message?
"A system error occurred. Please try again."
This is a generic error message so could be set off by any number of things. But I've encountered it most often when trying to upload a creative that includes Embedded OpenType fonts. I should add here that I am talking about creatives provided by third parties, not creatives that I have made myself.
You can check whether this is the problem with your creative by using the free online tool called CheckFileType. Upload your file, click 'Check File Type', and after a few seconds you will get a message a bit like this:
Here you can see that the GIF I uploaded indeed contains "Embedded OpenType (EOT)" fonts.
I'm no fonts expert so I'm not entirely sure why Google Ad Manager won't accept creatives that have Embedded OpenType fonts within them. However I understand that EOT is a legacy Microsoft format that is only supported by Internet Explorer (not even Microsoft Edge).
So it may be that Google Ad Manager blocks EOT fonts to ensure that your creative will display consistently across all browsers. That's nice, but it should really tell you as much when it refuses to accept it.
Here's what I do when I'm given a creative that contains EOT fonts.
That's it! This process removes the EOT fonts and you will now be able to upload the creative to GAM. And there's something fitting about using a legacy option to deal with a legacy format.
Bonus tip - if you don't have access to PhotoShop, you can use the free online tool Pixlr X to save off a PNG that will also work in GAM.