I always have this problem since I've installed Ubuntu One on my new Windows 7 computer. In the position circled in red there should be a button for log-in/out. How can I fix this?
This is a known bug: https://bugs.launchpad.net/ubuntuone-client/+bug/852107
Apparently this problem is caused by being behind a proxy or using firewall.
Make sure Ubuntu One is allowed in your firewall.
If you are using a proxy, Ubuntu One does not currently support proxies (but make sure you have latest version!).
Also, try this fix:
I had the same problem on my pc running Windows7 ultimate 64bit. I found out that the problem was an error on Windows firewall. It couldn't be turned on, as it was disabled. It had to be re-enabled, so I did it and it worked for me. I hope it'll work for you too:
Download and install ubuntu one again. It should work fine. Now you can turn off the windows firewall if you use another firewall software.
You should add all *.exe files (placed in .../ubuntuone/dist folder) to your Windows Firewall exceptions. After that you can disable firewall service if you want.
When Windows Firewall is enabled, some tabs may not work (devices, account info), but it will still sync your folders.
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