This was how i resolved this issue. First i followed the @helgans comment under his answer and still kept getting the reference to version 1.0.0 of system.web.optimization in the reference folder. I also deleted the dll from the bin folder of my website and reference version 1.1.0 from another project, yet the same problem persist.
In solving the problem, I discovered that the older version was being copied from the library folder in my application (well i do not know how). This makes the referenced version remain version 1.0.0, even if i referenced version 1.1.0 from another project or re-install the NuGet package again.
To solve this problem, i did the following:
- I deleted the dll from the Library folder.
- Removed the reference of the older version (thanks to @helgans)
- Removed the dll from the bin folder
- Unistall the package:
Uninstall-Package Microsoft.AspNet.Web.Optimization -Force
- Re-install the package
The NuGet now adds reference to version 1.1.0