My iCloud Photo Stream is not syncing correctly to my Windows 8.1 laptop or my Windows 7 PC.

I have been going through the forums for the last few weeks and nothing has helped. Both computers are x64 bit.

Problems I am experiencing

A. Windows 7 PC has not synced photo stream since September 25

B. Windows 8.1 laptop has not synced since a little before that.

C. I can't upload any photos (.jpegs) to the photo stream. An error pops up saying that they cann't be uploaded as they are not in a format supported by iCloud, even though they are jpegs.

D. Photos are syncing ti my ipad 3 perfectly fine, so clearly there is a problem with my computers but I am totally stumped.

1. I have un-installed, deleted all icloud photo stream folders, restarted and then re-installed the iCloud control panel on both computers, and it has created new folders and re-synced maybe 30 photos before it stopped again.
2. I have uninstalled every single Apple program on my Windows 8.1 laptop and reinstalled iTunes, iCloud and Quicktime and that didn't help.
3. I have toggled the Photo Stream on/off button in setting on my iphone, and that seemed to kick start the sync on my Windows 7 PC this morning, so far I've got 70 photos on my Windows 7 PC and that's where it has stopped but its a really random selection, and doesn't include the photos I took yesterday or today.
4. Two of my colleagues at work where my Windows 7 PC is located - their photo streams are working fine, both using ios7 and icloud control panel, however their computers are x32 bit.
5. I have also simply logged out and signed in again multiple times, however that doesn't do anything.
6. I have unticked the "read-Only" permissions on my photo icloud stream folder, but that didn't help either.
7. I have followed the troubleshooting from here: http://support.apple.com/kb/TS3989 - however that also did not help.
8. I have tried changing the folder path for iCloud photo stream, however that did not help either.
9. I tried the steps from someone who said they spoke to an Apple rep (steps copied from forum and I put them in italic) on this forum: https://discussions.apple.com/thread/5381738

   1. Anyway, the Apple rep had me sign out of iCloud CC on my PC.

   2. Then on each iOS devices Settings/iCloud/Delete Account.

   3. Confirmed all the warnings.

   4. Then re-entered my iCloud id and password on the iOS device.

   5. Things restarted and the iOS Photo Streams got loaded with the number of photos that

   6. iCloud has.

   7. Signed in on iCloud on the PC. It synced the same way.

   8. Tried taking pictures on the iPhone and iPad. They synced everywhere.

   9. So I'm back in business.

   10. I just deleted everything on my iOS devices when I exited iCloud.

   11. My interest is the PC syncing when I take a photo on my iPhone.

   12. ME: Okay so these steps again refreshed the photostream on my iPhone 5. I can see that the photos I took yesterday and today have been uploaded to the photo stream as I can see them there on my device. I have also now signed back into iCloud on my Windows 7 PC and it is slowly syncing again, but just recognising the same photos it downloaded previously as per Step 3 which I did just earlier this morning.

10. I have also just tried uploading photos via the upload folder from my windows 7 PC, and they uploaded perfectly.

This is really, really frustrating. I've tried everything I can find on these forums but nothing has helped fix the issue 100%.

Can anyone offer something else I can try to reslove this issue?