The "dotless" handler has a bad "ManagedPipelineHandler" module in its list of modules

Question

When I want to use dotless ( http://www.dotlesscss.org/ ), I have a problem:

When I try to request the file http://localhost/static/css/StyleLess.less , I get an HTTP error:

The "dotless" handler has a bad "ManagedPipelineHandler" module in its list of modules.

• MVC 4
• asp.net 4.0
• Classic IIS 7 Mode

However, if the application pool is set to Integrated, I have no problem.

I tried to use, among others

• How to get rid of this error Handler "PageHandlerFactory-Integrated" has a bad module "ManagedPipelineHandler" in its list of modules
• How to fix it: Handler "PageHandlerFactory-Integrated" has a bad module "ManagedPipelineHandler" in its list of modules

without success

Answer 1

Changing the application pool mode from Classic to Integrated helped me and solved this problem.