i have a board nucleo-L452RE-p i installed the package keil.STM32L4xx_DFP.2.3.0 on my keil MDK, i have also installed the STM32CubeL4 package from ST's website.but when i try to start a new project, my processor family is not there in the board selector page. i've added the screen shots for the above problem too, please help me out.
If you create a throw-away project (for any device), do you see the STM32L4xx_DFP installed, or any other pack you've installed? (Check using Project > Manage > Select Software Packs.., which is only available when a project is open.) Is your uVision installed in a non-standard location? Do you see the downloaded pack in Windows Explorer under %LOCALAPPDATA%\Arm\PACK\Keil? (That's the path that your pack installer seems to be using.)
I have a plain vanilla installation of MDK 5.29 in C:\Keil_v5, the STM32L4xx pack installed without any issues, and I can create a project that targets the '452 as well. That suggests it's an issue with your local installation, not the pack.
i checked the windows explorer directory you mentioned and the pack was there. the issue was with the installation hence i uninstalled everything related to keil and did a fresh install with a fresh licence and it worked. my MCU is visible now. thanks for the help.