Just Happened ... it was working fine ... issue with Android Studio 2.3.3 : Iam getting the following error... 
I am new at this and hate to mess with the gradle or any file ... can anyone please help...

the errors:

"


The SDK platform tools version (25.0.6) is too old to check APIs compiled with API 26; please update
This check scans through all ANDroid API calls in the application and  warns about any calls that are not available on all versionstargeted by the application (according to its minimum SDK attribute in the manifest).
If you really want to use this API and don’t need to support older devices just set the minSdkVersion in the build.gradle or AndroidManifest.xml files
If your code is deliberately accessing newer APIs and you have ensured (e.g. with conditional execution) that this code will only ever be called on a supported platform, then you can annotate you class or methodwith the @TargetApi annotation specifying the local minimum SDK to Apply, such as @TargetApi(11), such that this check considers 11 rather than you manifest file’s minimum SDK as the required API level.  
If you are deliberately setting android: attributes in style definitions, make sure you place this in values-xxx folder in order to avoid running into runtime conflicts on certain devices where manufacturers have added custom attributes whose ids conflict with new ones or later platforms.
Similarly, you can use tooltargetApi=”11” in an XML file to indicate that the elements will only be inflated in an adequate context."

I also get the package name up top as an error, but i just created the new App and even though it indicates an error.  it compiles and runs on the emulator on the targeted device.

Help.

