diff --git a/views/bootstrap/class.DocumentVersionDetail.php b/views/bootstrap/class.DocumentVersionDetail.php
index 99317fe7c..d4256223a 100644
--- a/views/bootstrap/class.DocumentVersionDetail.php
+++ b/views/bootstrap/class.DocumentVersionDetail.php
@@ -83,6 +83,7 @@ class SeedDMS_View_DocumentVersionDetail extends SeedDMS_Theme_Style {
 
 	function preview() { /* {{{ */
 		$dms = $this->params['dms'];
+		$settings = $this->params['settings'];
 		$document = $this->params['document'];
 		$timeout = $this->params['timeout'];
 		$xsendfile = $this->params['xsendfile'];
@@ -130,7 +131,7 @@ class SeedDMS_View_DocumentVersionDetail extends SeedDMS_Theme_Style {
 			case 'application/pdf':
 				$this->contentHeading(getMLText("preview"));
 	?>
-				<iframe src="../pdfviewer/web/viewer.html?file=<?php echo urlencode('../../op/op.ViewOnline.php?documentid='.$version->getDocument()->getID().'&version='.$version->getVersion()); ?>" width="100%" height="700px"></iframe>
+				<iframe src="<?= $settings->_httpRoot ?>ext/pdfviewer/res/web/viewer.html?file=<?=  urlencode(getBaseUrl().$settings->_httpRoot.'op/op.ViewOnline.php?documentid='.$version->getDocument()->getID().'&version='.$version->getVersion()); ?>" width="100%" height="700px"></iframe>
 	<?php
 				break;
 			case 'image/svg+xml':
diff --git a/views/bootstrap/class.ViewDocument.php b/views/bootstrap/class.ViewDocument.php
index c650418a7..93475228b 100644
--- a/views/bootstrap/class.ViewDocument.php
+++ b/views/bootstrap/class.ViewDocument.php
@@ -615,7 +615,7 @@ $(document).ready( function() {
 					$this->contentHeading(getMLText("preview"));
 ?>
 			<div style="width:100%; height: 0; position:relative; padding-top: 141%;">
-			<iframe src="<?= $settings->_httpRoot ?>ext/pdfviewer/res/web/viewer.html?file=<?php echo urlencode($settings->_httpRoot.'op/op.ViewOnline.php?documentid='.$latestContent->getDocument()->getID().'&version='.$latestContent->getVersion()); ?>" _width="100%" _height="100%" style="position: absolute; top: 0; left: 0; bottom: 0; right: 0; width: 100%; height: 100%"></iframe>
+			<iframe src="<?= $settings->_httpRoot ?>ext/pdfviewer/res/web/viewer.html?file=<?php echo urlencode(getBaseUrl().$settings->_httpRoot.'op/op.ViewOnline.php?documentid='.$latestContent->getDocument()->getID().'&version='.$latestContent->getVersion()); ?>" _width="100%" _height="100%" style="position: absolute; top: 0; left: 0; bottom: 0; right: 0; width: 100%; height: 100%"></iframe>
 			</div>
 <?php
 					break;
@@ -652,7 +652,7 @@ $(document).ready( function() {
 					$this->contentHeading(getMLText("preview_pdf"));
 ?>
 				<div style="width:100%; height: 0; position:relative; padding-top: 141%;">
-				<iframe src="<?= $settings->_httpRoot ?>ext/pdfviewer/res/web/viewer.html?file=<?php echo urlencode($settings->_httpRoot.'op/op.PdfPreview.php?documentid='.$latestContent->getDocument()->getID().'&version='.$latestContent->getVersion()); ?>" _width="100%" _height="700px" style="position: absolute; top: 0; left: 0; bottom: 0; right: 0; width:    100%; height: 100%"></iframe>
+				<iframe src="<?= $settings->_httpRoot ?>ext/pdfviewer/res/web/viewer.html?file=<?php echo urlencode(getBaseUrl().$settings->_httpRoot.'op/op.PdfPreview.php?documentid='.$latestContent->getDocument()->getID().'&version='.$latestContent->getVersion()); ?>" _width="100%" _height="700px" style="position: absolute; top: 0; left: 0; bottom: 0; right: 0; width:    100%; height: 100%"></iframe>
 				</div>
 <?php
 				}