Critical error after rebuilding search index

[Karmann]

The search function did not work well on my forum, so I tried changing it to sphinx and rebuilding search index, but now my site says:

"Critical Error We are currently experiencing technical difficulties. Please check back in 24 hours."

I'm still able to access CP, but I'm not sure what can be the cause of this.

[Mark.B]

Have you actually got Sphinx installed on the server?
That option is only applicable if you have.
Otherwise, you need to change that setting back.

[Karmann]

Have you actually got Sphinx installed on the server?
That option is only applicable if you have.
Otherwise, you need to change that setting back.

Sorry, I did not know that. I tried rebuilding with the old setting and it seems to work, even thought it's not finished. I guess I needed just to rebuild search after my upgrade from VB4