magento theme falling back to default theme even after theme is changed in admin side. I am trying to change theme from default to blank theme under default package . I tried clearing all cache and checked System > Configuration > GENERAL > Design > Themes > Layout, it is "blank" and System > Configuration > GENERAL > Design > Package > Current Package Name is "default".
Falling back is totally fine. If magento doesn't find the template it is looking for, it falls back to default/default and checks for the template there, or did I understand you wrong?
Because of this it is called fallback.
It sounds like you could be having an issue with the store scope. While in the admin System > Configuration in the upper left hand corner you'll see "Current Configuration Scope" with a drop down. Here you can select the Default Config, website view, or individual store views.
If you want to use Magento's multi store capabilities you would want to set your theme and package under the individual store view. Or for example if you wanted to have a different design for different languages.
Click the drop down and select the store view then in the main area expand Package and Themes. You can choose to set your package and theme here if it is appropriate to your web needs OR if you plan to only have one design for your store (for all stores and languages for example) then check the box for "Use Website" next to Current Package Name Templates Skin (Images/CSS) Layout Default
Now click save.
You may need to repeat this process for the "Main Website" view in the Current Configuration Scope also.
Once done go back to "Default Config" under the Current Configuration Scope ensure that: Current Package Name is "default" Templates is "blank" Skin(Images/CSS) is "blank" Layout is "blank" Default is "default"
All with no quotation marks around them of course.