ShipScript has been an eBay Community volunteer since 2003, specializing in HTML, CSS, Scripts, Photos, Active Content, Technical Solutions, and online Seller Tools.
What does the text of the error message say? Does it mention only images?
I think google drive will work, or even dropbox, but don't have either service myself. There are two typical problems with free photo hosting sites: 1) they may be password protected, so the files and folders must be made public, or access will be denied; and 2) the link to the photo may actually be a link to a webpage instead of a link to a bare photo, so eBay's server will see invalid content when expecting a photo.
The webpage link is quite a prevalent problem. When looking for the source code for an image, you may need to view the webpage that displays the embedded image and then copy the image URL from the source. Some sites will actually provide the raw image URL that you can copy directly.
Once you get your upload working in your test environment, I assume you plan to use real photos instead of a stock photo. When uploading multiple photos, all photos for one listing must be in a single cell and must be separated with the vertical pipe delimiter ( | ), with no intervening spaces.
If the seller's photo server is underpowered, uploading too many photos in too large a batch may cause problems, as the server can't respond as fast as eBay makes requests. In those instances, the photos never transload to eBay and are, instead, served to the listing directly from the hosting server. Those photos may take a long time to load when the listing is opened and will not have the zoom feature.
Google should not have a delivery problem, but if you find any non-transferred photos when using other smaller hosting services, it's always a good idea to try to upload them again.
An alternate approach to uploading all photos through File Exchange is to go ahead and upload a single online placeholder image with the listings. Then, after the upload is successful, revise each listing to delete the photo and upload photos directly from the desktop.
eBay does not normally allow uploading images from their own server back to their own server, but it might work somewhat through File Exchange, where an error will display, yet the listings might post with or without the image. And you don't care whether it posts without the image because you will be immediately fixing those listings.
If the image uploads successfully, then eBay has simply reused the URL; and when the original source image disappears from eBay, so will the photos that were reused in other listings. And that is why we don't upload eBay-hosted photo urls to new listings.
Here is the 600 px size of your eBay-hosted store logo. It may or may not load through File Exchange.
https://i.ebayimg.com/images/g/m-sAAOSwo3tauU~t/s-l600.jpg
Try only one and then see if you can revise your listing manually through the app. eBay doesn't allow a mix of sources (online urls vs local upload) in many cases, so test whether deleting all photos in your revision will allow you to supply the new photos from your phone. There have been instances where the mix of sources has been allowed, but eBay has been playing with the photo hosting this past year and I have not fiddled with all the scenarios. You'll have to be the guinea pig here.
