?flush=all or ?flush=1 does not work in any situation. everything else seems to be working fine.
Has anyone had this happen before or know what might be causing this?
I have no idea...

I've never encountered it just 'not working'. I had some issues where erights were not set properly on building the silverstripe-cache for the first time, so that I got a 'not writable' error each time I used ?flush, but...

So no errors? And your template (or yaml) changes are never aplied? Do you have the silverstripe-cache directory in your site root and is it writable?

thanks martimiz, would have never noticed that.
So the silverstripe-cache didnt exist so ive created it. ran dev/build?flush=all and the cache has been populated with files. however all I get in dev/build is an 'Enviroment Builder' title along with my base url and dev breadcrumbs but nothing else.

So no list of database tables and fields? Might be an error along the way, that isn't displayed... Is your site in dev mode? Is your php.ini set to report errors? Uncle Cheese has a page on debugging SilverStripe on his site:

http://www.leftandmain.com/silverstripe-tips/2010/09/08/8-common-silverstripe-errors-explained-and-solved/

I'm not sure if it includes v3.x but it might give you some clues

Note: basically the flush bit is what updates the SilverStripe cache files, the dev/build is what builds the database table. The combi does all :) If the silverstripe-cache dir is missing, SilverStripe will use the tmp directory, that doesn't always work well.

Its strange, the database was generated, site was set to dev mode, php.ini was set to report errors and I had a look at the 8 common erros a few time and it didnt help. Dev/build works on its own but with ?flush=all or ?flush=1 it failed. (Had been trying to flush when adding a couple of modules)

I ended up doing another clean install and this time it seems to work. I did noticed that my url would not redirect from mydomain.com.au/silverstripe/ to mydomain.com.au/silverstripe/install.php like normal, as i found this is in the .htaccess file but it seems to be ignored.

When re-installing there were no errors in the installer. but it didnt create silverstripe-cache again, had to do that manually. It does seem to be all working fine at the moment. so thanks for your help @martimiz.

I ended up here after a search on Google, so I thought I'd share the solution to a similar problem I had.

I just upgraded to php 5.6, and all my SilverStripe installations stopped working, displaying only a fatal error (some memory overflow while in Core.php I believe). Calling flush=all solved the issue on half of the sites, but for the others that simply didn't do anything. I ended up removing the cache folders manually, which by default are located under /tmp/ with names such as /tmp/silverstripe-cache-*

Great that you have everything working again!

I always add the silverstripe-cache directory to the root of my websites. This will Make SilverStripe automatically use it, and I find it far better to maintain, then finding out where the tmp dir is all the time. On a PHP upgrade nowadays I always just empty the cache by hand, to avoid problems - but some may have reasons to not want to do that.

Still - I strongly object to providers doing major software upgrades without informing the users. But some do....

Note: In contrary to what I said above in ss3.1 doing a /dev/build?flush=1 doesn't seem to automatically flush the cache anymore.

I'm having an issue with ?flush=all also. It is on a site migrated from ss2.4->ss3.1.13. On my local mamp it flushes fine, but on the production server it does not. The cache folder (site root/silverstripe-cache) fills up, but the site just throws an unspecified error. I've tried turning on all error reporting I can think of, but just get a 'Sorry, there was a problem with handling your request.'

The cache folder has full write permissions...I've been through and removed a few closing php tags, but just can't seem to get it working.