error regarding flex n bison on visual studio2010

[Ankit Pal]

 hello sir\madam,

                               i request you that i have a problem while i
m compiling a flex n bison file on visual studio2010  then it gives a error
in flexbisn.targets file..as follows



1>  Generating lexical analyser...
1>D:\software\flexbison rules\FlexBison.targets(55,5): error MSB3686:
Unable to create Xaml task.  Compilation failed.
1>D:\software\flexbison rules\FlexBison.targets(55,5): error MSB3686:
Source file 'C:\Windows\TEMP\fxy2fh1x.0.cs' could not be found
1>D:\software\flexbison rules\FlexBison.targets(55,5): error MSB3686: No
inputs specified
1>D:\software\flexbison rules\FlexBison.targets(55,5): error MSB3686:
1>D:\software\flexbison rules\FlexBison.targets(55,5): error MSB4036: The
"FlexGenerator" task was not found. Check the following: 1.) The name of
the task in the project file is the same as the name of the task class. 2.)
The task class is "public" and implements the
Microsoft.Build.Framework.ITask interface. 3.) The task is correctly
declared with <UsingTask> in the project file, or in the *.tasks files
located in the "C:\Windows\Microsoft.NET\Framework\v4.0.30319" directory.
1>
so plz help me sir .. thanks