http://technet.microsoft.com/en-us/library/cc561139.aspxHave you looked at this anyway? The paths would see relatively easy to fix, but you have to remember once you get down to below 4GBs, your server will act erratically. Does Exchange work. It is usually the first to go.
Are the files that are on C:\ drive the metadata files for the WSUS files?
Here is another thought: Right click on My Computer, Properties, Advanced System Settings, Advanced, Performance settings, Performance options, Advanced. How large is your paging file? It shouldn't be on your C drive anyway. Best practices would say make the paging file 1.5 times your RAM. That could free up some space.
Download a program called TreeSize. This is a must have program, which after running will show all of your data and files in tree form, so you can see if there are any folders that are too big. Of course, you kind of already know. I was once down to 5GBs, ran TreeSize and found a 32GB backup, which I deleted. 37GBs now were there.
Amazing Chart Service is not running on your server is a bug from over a year ago, you just click through it. Apparently, AC doesn't find it annoying enough to fix it.
Another thing, whether Sandeep or I or Indy can fix this, your main concern right now is your 1.5GBs of space. Maybe the page file can fix that. But, your server is going to stop running. You may want to consider moving AC to another computer temporarily.
Finally, I know that $257 is a bit pricey, but in the scheme of things at least you know you will fix the WSUS and size issue. Microsoft WILL FIX THIS. I would have called them today. They will remote in and work through the night if necessary. Of course, you can't call them on the weekend or they will charge you $500. But, there is an issue with temp files and WSUS. Like you said, you already moved it as best practices would say, although I don't move those things, and I leave the WSUS files on the net. So, something is strange and maybe Sandeep who rocks can fix it, but as far as the WSUS and why it is showing up on the C:\ drive will be corrected 100% by Microsoft. Personally, I have never seen any better support in the world than Microsoft's.
And, finally #2, I wouldn't hold your breath for senior help. I don't mean that in a mean way. AC can likely fix the path issue, but they are not going to understand the WSUS issues, and my guess he/she will just tell you that it isn't compatible with SBS 2011, which, of course, is crazy.
