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I am logged in. I just found I could upload the file if I reduced the quality to Medium. at 96 ppi.
But to check to be sure, I just signed out and logged in and repeated the upload at 96ppi and high quality.
I had exactly the same results as I described in the original posting. It feels like the server is baulking at the high quality setting.
Many thanks to the Development Team for fixing what ever it was that caused the uploading errors in the last few days.
This morning I am able to upload with 144 ppi and maximum quality.
I also tried to publish a "test"-file with this new feature ... but i got the same error message like jhsca.
I tried to log out and log in.
Do you have other suggestions?