download elgg same version again and upload mod folder from that and run <yoursite>/upgrade.php

What version of elgg are you using?

Arvixe/Elgg Community Liaison

I tried with same version (1.8) MOD folder, but it appear all plugins are disabled and can't be enabled... I ran ugrade as well.... still no luck...

can I see you site?

www.iracebook.net 

This is what I see after running upgrade when trying to look at the plugins

community3_theme (guid: 43) cannot start and has been deactivated. Reason: Cannot include start.php for plugin community3_theme (guid: 43) at /homepages/18/d276598355/htdocs/social_network/elgg/mod/community3_theme.

garbagecollector (guid: 12) cannot start and has been deactivated. Reason: Cannot include start.php for plugin garbagecollector (guid: 12) at /homepages/18/d276598355/htdocs/social_network/elgg/mod/garbagecollector.

htmlawed (guid: 14) cannot start and has been deactivated. Reason: Cannot include start.php for plugin htmlawed (guid: 14) at /homepages/18/d276598355/htdocs/social_network/elgg/mod/htmlawed.

invitefriends (guid: 15) cannot start and has been deactivated. Reason: Cannot include start.php for plugin invitefriends (guid: 15) at /homepages/18/d276598355/htdocs/social_network/elgg/mod/invitefriends.

likes (guid: 16) cannot start and has been deactivated. Reason: Cannot include start.php for plugin likes (guid: 16) at /homepages/18/d276598355/htdocs/social_network/elgg/mod/likes.

logbrowser (guid: 17) cannot start and has been deactivated. Reason: Cannot include start.php for plugin logbrowser (guid: 17) at /homepages/18/d276598355/htdocs/social_network/elgg/mod/logbrowser.

logrotate (guid: 18) cannot start and has been deactivated. Reason: Cannot include start.php for plugin logrotate (guid: 18) at /homepages/18/d276598355/htdocs/social_network/elgg/mod/logrotate.

members (guid: 19) cannot start and has been deactivated. Reason: Cannot include start.php for plugin members (guid: 19) at /homepages/18/d276598355/htdocs/social_network/elgg/mod/members.

messages (guid: 21) cannot start and has been deactivated. Reason: Cannot include start.php for plugin messages (guid: 21) at /homepages/18/d276598355/htdocs/social_network/elgg/mod/messages.

oauth_api (guid: 23) cannot start and has been deactivated. Reason: Cannot include start.php for plugin oauth_api (guid: 23) at /homepages/18/d276598355/htdocs/social_network/elgg/mod/oauth_api.

That seems like elgg can't find those plugins, and has deactivated it.  Are you sure you've re-uploaded the mod directory to the right place?

Weird. May be you need to do a reinstallation.

Rodolfo Hernandez
Arvixe/Elgg Community Liaison

Ok getting there, take a look now, but I still get the above by plugins that are present in the mods folder but dont show up in the plugin enable menu

Have you looked deeper into those plugins to make sure that the files got uploaded as well, maybe they're just empty directories in the mod folder?  The error that's being reported is that it can't include the start.php of each one.  Make sure that there is indeed a start.php in there.  Refresh your FTP, sometimes it can show you things that are no longer there due to caching (I get that in FireFTP).