IAP broken - can't reinstall

Hi
I am getting this error when I try to reinstall the IAP package:
the unity iap installed has been cancelled
this installer is corrupt and is missing one or more components
I have tried
deleting the UnityPurchasing folder under plugins
reimporting from the services tab
removing from the package manager

when i try to import again from Package Manager I get this message:
The Unity IAP installer will determine if your project is configured properly before importing hte unity IAP asset package
Would you like to run the Unity IAP installer now?

When I do, I get the same error as at the top of this post

When I look in the UnityPurchasing folder i just have one file ETag

any ideas?
thanks

 

anyone with the same problem - check your directory structure. Unity was lagging badly when i moving files and looks like the plugin got moved to a different directory. I then deleted everything and started again and seems to be working