PNG files don’t synch on SkyDrive

I'm part way through a 30 day trial of Office 365 and am using SkyDrive.

I have a number of PNG files which are marked with a red cross in my local SkyDrive folder. Word and Visio docs synch fine.

I've looked at the synch lo and it says "We couldn't sunc some files or folders" and

"We’re having trouble downloading this file. It may be too large or there may be a network connectivity problem. Please try again later.

ICsiError: csierrInvalidURL (0x61)"

The six PNG files in question are 20KB or so and it's been happening for the last couple of days ... it's not a connectivity problem.

Any thoughts?

Thanks

Duncan

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