Someone in the office has a similar problem as this person:
http://community.office365.com/en-us/forums/146/p/74186/280168.aspx#280168
He uses Windows 8 (a UK English installation) with Office 2010 Pro (Dutch).
He can open files from our Office 365 storage but can't save them through Office. It gives identical errors as in the above thread.
When I open a file from Office 365 and make an edit and press the save button on top it prompts the save as dialog.
I have to enter a new file name and it gives me after I press save in that dialog a yellow warning bar that reads in Dutch 'Upload Failed , The changes have been stored, but can't be uploaded because of an error. You could possibly upload this file through the serverwebpage. [Save a copy]'
In Office Upload Center it says (in Dutch) as status 'Upload failed' , 'Upload error'
When I login under his credentials on my own computer at home running Windows 8 Pro (UK English), Office 2010 Home and Home Business I don't run into any problems.
I have run the Office 365 installation app to setup the computer. But to no avail.