I have trouble with DotNetNuke version 3.0.11

I put folder DotNetNuke in C:\Inetpub\wwwroot

When I build its solution, I usually get this error:

" Unable to write to output file 'C:\Documents and Settings\Administrator\VSWebCache\ELEAD\DotNetNuke\obj\Debug\DotNetNuke.dll': The process cannot access the file because it is being used by another process.

Unable to write to output file 'C:\Documents and Settings\Administrator\VSWebCache\ELEAD\DotNetNuke\obj\Debug\DotNetNuke.pdb': Access is denied.  "

I can't repair it. If I want to continue, I must close all solution, and delete folder C:\Documents and Settings\Administrator\VSWebCache\ELEAD\DotNetNuke\ then open again this solution. But it's inconvenient

Please show me how to solve this trouble as soon as possible. Thank in advance
You can send direct your advices to my email: doquocbao@gmail.com

I think this is a common development issue with vswebcache - I looked around and could not figure out how to eliminate it either. I would just rename the vswebcache folder everytime I had to close down, so not to have to delete till later, saved me some time when developing but not a "solution"