FTP로 접속해서 스킨 파일을 수정해주세요.

/wp-content/plugins/kboard/skin/사용중인스킨/document.php 파일에서

아래 코드를 찾으신 다음

<div class="kboard-document-action">
	<div class="left">
		<button type="button" class="kboard-button-action kboard-button-like" onclick="kboard_document_like(this)" data-uid="<?php echo $content->uid?>" title="<?php echo __('Like', 'kboard')?>"><?php echo __('Like', 'kboard')?> <span class="kboard-document-like-count"><?php echo intval($content->like)?></span></button>
		<button type="button" class="kboard-button-action kboard-button-unlike" onclick="kboard_document_unlike(this)" data-uid="<?php echo $content->uid?>" title="<?php echo __('Unlike', 'kboard')?>"><?php echo __('Unlike', 'kboard')?> <span class="kboard-document-unlike-count"><?php echo intval($content->unlike)?></span></button>
	</div>
	<div class="right">
        ...
	</div>
</div>

아래 코드로 변경해보시겠어요?

<div class="kboard-document-action">
		<?php if(!$content->notice):?>
			<div class="left">
				<button type="button" class="kboard-button-action kboard-button-like" onclick="kboard_document_like(this)" data-uid="<?php echo $content->uid?>" title="<?php echo __('Like', 'kboard')?>"><?php echo __('Like', 'kboard')?> <span class="kboard-document-like-count"><?php echo intval($content->like)?></span></button>
				<button type="button" class="kboard-button-action kboard-button-unlike" onclick="kboard_document_unlike(this)" data-uid="<?php echo $content->uid?>" title="<?php echo __('Unlike', 'kboard')?>"><?php echo __('Unlike', 'kboard')?> <span class="kboard-document-unlike-count"><?php echo intval($content->unlike)?></span></button>
			</div>
		<?php endif?>
			<div class="right">
				<button type="button" class="kboard-button-action kboard-button-print" onclick="kboard_document_print('<?php echo $url->getDocumentPrint($content->uid)?>')" title="<?php echo __('Print', 'kboard')?>"><?php echo __('Print', 'kboard')?></button>
</div>

고맙습니다.