[MonoDevelop] Error when compiling projects from within monodevelop

[Andrew Gorcester]

Since upgrading to MonoDevelop 0.2 (in the process I upgraded all other
parts of my Mono install to the latest versions as well), I've been
unable to compile any projects.  Monodevelop reports the following when
I click the "build active project or buffer" button:

---
Error while compiling

Exception occurred: System.NullReferenceException: A null value was
found where an object instance was required.
in (unmanaged) (wrapper managed-to-native)
System.Diagnostics.Process:Start_internal
(string,string,intptr,intptr,intptr,System.Diagnostics.Process/ProcInfo_)
in <0x00004> (wrapper managed-to-native)
System.Diagnostics.Process:Start_internal
(string,string,intptr,intptr,intptr,System.Diagnostics.Process/ProcInfo_)
in [0x000c7] (at
/home/duncan/Mono/mcs/class/System/System.Diagnostics/Process.cs:698)
System.Diagnostics.Process:Start_common
(System.Diagnostics.ProcessStartInfo,System.Diagnostics.Process)
in [0x00007] (at
/home/duncan/Mono/mcs/class/System/System.Diagnostics/Process.cs:738)
System.Diagnostics.Process:Start ()
in <0x00057> (wrapper remoting-invoke-with-check)
System.Diagnostics.Process:Start ()
in [0x00075] (at
/home/andrewsg/source/monodevelop-0.2/src/AddIns/BackendBindings/CSharpBinding/CSharpBindingCompilerManager.cs:338) CSharpBinding.CSharpBindingCompilerManager:DoCompilation (string,System.CodeDom.Compiler.TempFileCollection,string_,string_)
in [0x005b1] (at
/home/andrewsg/source/monodevelop-0.2/src/AddIns/BackendBindings/CSharpBinding/CSharpBindingCompilerManager.cs:270) CSharpBinding.CSharpBindingCompilerManager:CompileProject (MonoDevelop.Internal.Project.IProject)
in [0x00007] (at
/home/andrewsg/source/monodevelop-0.2/src/AddIns/BackendBindings/CSharpBinding/CSharpLanguageBinding.cs:84) CSharpBinding.CSharpLanguageBinding:CompileProject (MonoDevelop.Internal.Project.IProject)
in [0x00294] (at
/home/andrewsg/source/monodevelop-0.2/src/Main/Base/Internal/Project/Combine/CombineEntry.cs:148) MonoDevelop.Internal.Project.ProjectCombineEntry:Build (bool)
in [0x00081] (at
/home/andrewsg/source/monodevelop-0.2/src/Main/Base/Internal/Project/Combine/Combine.cs:522) MonoDevelop.Internal.Project.Combine:Build (bool)
in [0x00043] (at
/home/andrewsg/source/monodevelop-0.2/src/Main/Base/Services/Project/DefaultProjectService.cs:252) MonoDevelop.Services.DefaultProjectService:CompileCombine ()
in [0x00080] (at
/home/andrewsg/source/monodevelop-0.2/src/Main/Base/Commands/RunCommands.cs:68) MonoDevelop.Commands.Compile:CompileThread ()
---

This happens even with a completely new GTK# project.

As a side note, where does MonoDevelop keep its user-specific
configuration?  I wanted to delete my configuration files for
MonoDevelop in case the problem stemmed from an incompatibility between
versions, but I can't find where the program puts them.

-Andrew