Rheingold standalone start error

Hi!

Can anyone hep me. I use rheingold 4.12.12 with latest sdp files, this working perfeckt. I changed this with 4.15 standalone version, i use rc cleaner 4.4, but the ista not start.

The error messege, is:

Failed to start ISTA.
Please make sure your ISTA configuration is valid.
In doubt reset any non standard ISTA configuration and reinstall ISTA.