@smhcis – Thanks for the report. So you actually got the error message “The plugin does not have a valid header.” I see it in quotes but have never seen a message like that before.
Did a quick google check and seems several other plugins have seen random instances of this error. So far I can’t find any that actually had a solution, which seems to mean its something related to either your install and other plugins or the hosting its on.
Nearly all tickets I read said that if they simply went to the plugins page they could activate without error, most only saw this issue on first install of a plugin.
That all said the 208 characters means there was a PHP error on activation, that we can do something about. Those errors are logged for all sites, if you can check your sites error logs and give me the errors then I can patch whatever needs to be fixed.
Hope that helps.
Hi, I tried to install it too and got same error.
I’m using, besides the design plugins, iThemes PRO, ManageWP Orion with Arcane theme from skywarriorthemes.com.
Could some of those plugins affecting your installation?
Thanks.
@erikggonc – Can you check the error logs, or ask your host for that?
Hi,
I’m getting the same error on activation. I couldn’t find any related entry in error_log but, after activating wp_debug, I get this:
Warning: Cannot modify header information - headers already sent by (output started at /home/myserver/mysite/wp-includes/functions.php:3891) in /home/myserver/mysite/wp-includes/pluggable.php on line 1179
Thanks.
Álvaro
@alvarogois – Hmm, just to be clear your site is running PHP 5.3+?
The problem is, even the error you got with WP Debug on doesn’t lead us anywhere. The 2 files its pointing to are WP Core files not this plugins.
There definitely has to be something off as there have been several reports. But even if you had an older unsupported version of PHP it should fail gracefully, that is to fail after activation by simply not initializing.
Can you post your PHP & WP versions so I can try to eliminate that as a possibility.
@danieliser: no, it’s an old install I’m updating, currently running WordPress 4.7.2 in my staging site, over PHP 5.4.45.
