I recently installed 5.6.1 and it seemed to work fine.

I also then installed some modules and skins, OWS, Forms, dnnblue etc

Somewhere along the line I am now missing modules eg hosts –module definitions, admin---- site settings.
Some I can work around but others not.

Has anybody else seen this and have a solution. They were definitely there at the beginning.

Are you missing modules or missing pages? Are you missing the host pages?

Did you install 5.6.1 from scratch, or was this an upgrade?

I ran into something similar recently, and was able to correct the issue by digging around inside of the database. Please provide more details and perhaps I can help you with this.

Not sure whether modules or pages.
Host -----Module definitions and admin---site settings are there in the drop down but only produce a blank page

Installed from scratch and seemingly no errors
They were there originally. I have reinstalled on a different server and all is well.
However I put some time and effort into configuring the original system only for these errors to occur and there seems no reason if i repeat the configuration why the same will not happen again.

John,

I would be surprised if something like that happens again, unless there is something done that gets repeated again.

My standard practice is to make a complete backup of the website's directory and database before starting any major work on a site. That is more to protect me from things that I do. And, once in production, it's always good to keep regular backups. Usually that can be done automatically. If there is "user contributed" data on a site, more frequent backups are a good idea.