oneumyvakin

Yes, it’s write permission issue.
On Plesk for Windows you need to set “Additional read/write permissions” in domain’s “Hosting Settings”.

I’ve get this issue at managing WordPress via wp-cli

The root cause in fact that $_SERVER[‘SERVER_NAME’] is empty in CLI mode:

\wp-includes\pluggable.php(352): PHPMailer->setFrom(‘wordpress@’, ‘WordPress’, false)

	if ( !isset( $from_email ) ) {
		// Get the site domain and get rid of www.
		$sitename = strtolower( $_SERVER['SERVER_NAME'] );
		if ( substr( $sitename, 0, 4 ) == 'www.' ) {
			$sitename = substr( $sitename, 4 );
		}

		$from_email = 'wordpress@' . $sitename;
	}

	/**
	 * Filters the email address to send from.
	 *
	 * @since 2.2.0
	 *
	 * @param string $from_email Email address to send from.
	 */
	$from_email = apply_filters( 'wp_mail_from', $from_email );

	/**
	 * Filters the name to associate with the "from" email address.
	 *
	 * @since 2.3.0
	 *
	 * @param string $from_name Name associated with the "from" email address.
	 */
	$from_name = apply_filters( 'wp_mail_from_name', $from_name );

	$phpmailer->setFrom( $from_email, $from_name, false );

_

it can be easily fixed by changing in /wp-content/plugins/nextgen-gallery/nggallery.php call load_plugin_textdomain to:

function _register_hooks()
	{
		// Load text domain
		load_plugin_textdomain(
			NEXTGEN_GALLERY_I8N_DOMAIN,
			true,
			plugin_basename($this->directory_path('lang'))
		);

Looks like it happens because of absolute path to mo file concatenated with path to plugin dir:

/wp-content/plugins/nextgen-gallery/nggallery.php

function _register_hooks()
	{
		// Load text domain
		load_plugin_textdomain(
			NEXTGEN_GALLERY_I8N_DOMAIN,
			true,
			$this->directory_path('lang')
		);

$this->directory_path(‘lang’) – returns like ‘C:\Inetpub\vhosts\domain.tld\httpdocs\wordpress\wp-content\plugins\nextgen-gallery\lang’

because it get path from __FILE__ constant.

and than in /wp-includes/l10n.php

function load_plugin_textdomain( $domain, $abs_rel_path = false, $plugin_rel_path = false ) {
	$locale = apply_filters( 'plugin_locale', get_locale(), $domain );

	if ( false !== $plugin_rel_path	) {
		$path = WP_PLUGIN_DIR . '/' . trim( $plugin_rel_path, '/' );
	} else if