Weird
Try enabling three of them until you pin the one that's giving problems. Next check if you have the most recent version of these plugins.
If you keep running into troubles report back to this topic.

Good luck

yeah, nothing seems to be working. even if i restore to defaults and don't mess with any of the settings, they keep disabling...

One annoying thing about plugins is that the disable *seems* to cascade .... anyway, that's beside the point

You might like to try upping the memory limit in ... urm, some conf file, /conf/_advanced.php ... I think

¥

didn't see anything specific in advanced.php that really had to do with plugin size... just file uploading size which i already have at 100mb.

The YouTube plugin is giving me the exact same problem: [url=http://forums.b2evolution.net/viewtopic.php?t=17130]Forum post[/url] - it's the only one I've installed, but it's certainly giving me trouble

What does Dashboard -> Tools -> System say about the PHP memory limit. You can change that in your php.ini

Good luck

Dashboard -> Tools -> System says "PHP memory_limit
n.a."

php.ini says "memory_limit = 20M"

Not sure why there's a discrepancy..