I am unable to install ghostdoc.
The error message is "Microsoft Visual Studio.NET is not installed on your computer"
Visual Studio is installed on my computer.
Have you seen this problem? Is there a workaround? Is there a way to install ghostdoc by hand?
There are multiple versions of the .Net framework. It's possible that ghostdoc is requiring a particular version of the .Net framework than is being provided by Visual Studio.
Your question is tagged with VS 2010 so I assume that's the version installed. If so then it only guarantees that the 4.0 .Net Framework is installed on the machine. Given that 4.0 is very new it's possible ghostdoc depends on the 2.0 and hence raises an error since 2.0 is not installed.
I would consult the ghostdoc manual and see which particular version it requires.