Index: openacs-4/packages/file-storage/file-storage.info
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/file-storage/file-storage.info,v
diff -u -N -r1.60.2.11 -r1.60.2.12
--- openacs-4/packages/file-storage/file-storage.info	6 Apr 2021 19:16:16 -0000	1.60.2.11
+++ openacs-4/packages/file-storage/file-storage.info	19 Apr 2021 13:01:13 -0000	1.60.2.12
@@ -7,7 +7,7 @@
     <initial-install-p>f</initial-install-p>
     <singleton-p>f</singleton-p>
 
-    <version name="5.10.0d12" url="http://openacs.org/repository/download/apm/file-storage-5.10.0d12.apm">
+    <version name="5.10.0d13" url="http://openacs.org/repository/download/apm/file-storage-5.10.0d13.apm">
         <owner url="http://openacs.org">OpenACS</owner>
         <summary>Collaborative document storage</summary>
         <release-date>2017-08-06</release-date>
@@ -17,7 +17,7 @@
         <maturity>2</maturity>
         <package_instance_name>#file-storage.file-storage#</package_instance_name>
 
-        <provides url="file-storage" version="5.10.0d12"/>
+        <provides url="file-storage" version="5.10.0d13"/>
         <requires url="acs-kernel" version="5.9.1"/>
         <requires url="acs-tcl" version="5.10.0d38"/>
         <requires url="acs-content-repository" version="5.10.0d14"/>
@@ -26,7 +26,6 @@
 
         <requires url="categories" version="1.1.3"/>
         <requires url="notifications" version="5.9.1"/>
-        <requires url="oacs-dav" version="1.1b1"/>
         <requires url="rss-support" version="0.5d1"/>
 
         <callbacks>
@@ -52,7 +51,7 @@
             <parameter datatype="number"  min_n_values="1"  max_n_values="1"  name="ShowAdministerPermissionsLinkP"  default="1" description="Whether or not to show a link to administer permissions on the file storage object."/>
             <parameter datatype="number"  min_n_values="1"  max_n_values="1"  name="StoreFilesInDatabaseP"  default="0" description="Flag to determine the storage type. A flag of 1 (true) will store the files in the database. If 0 (false) files are stored in the filesystem. ***This parameter should only be changed at package instance creation.***"/>
             <parameter datatype="string"  min_n_values="1"  max_n_values="1"  name="UnzipBinary"  default="unzip" description="The path and name of the unzip binary to unpack zip files containing multiple files."/>
-            <parameter datatype="number"  min_n_values="1"  max_n_values="1"  name="UseWebDavP"  default="0" description="Flag to determine if WebDav is active.  A flag of 1 (true) means WebDav is active and we will show WebDav links"/>
+            <parameter datatype="number"  min_n_values="1"  max_n_values="1"  name="UseWebDavP"  default="0" description="Flag to determine if WebDav is active.  A flag of 1 (true) means WebDav is active and we will show WebDav links. oacs-dav package must be installed for this flag to have any effect."/>
         </parameters>
 
     </version>
Index: openacs-4/packages/file-storage/tcl/file-storage-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/file-storage/tcl/file-storage-procs.tcl,v
diff -u -N -r1.90.2.20 -r1.90.2.21
--- openacs-4/packages/file-storage/tcl/file-storage-procs.tcl	12 Apr 2021 08:36:10 -0000	1.90.2.20
+++ openacs-4/packages/file-storage/tcl/file-storage-procs.tcl	19 Apr 2021 13:01:13 -0000	1.90.2.21
@@ -1213,6 +1213,17 @@
     return $parent_id
 }
 
+ad_proc -private fs::webdav_p {} {
+    Returns if webDAV is enabled.
+
+    @return boolean
+} {
+    return [expr {
+                  [parameter::get -parameter "UseWebDavP" -default 0] &&
+                  [apm_package_installed_p oacs-dav]
+              }]
+}
+
 ad_proc fs::webdav_url {
     -item_id:required
     {-root_folder_id ""}
@@ -1227,7 +1238,7 @@
             item is not WebDAV enabled
 } {
 
-    if {  [parameter::get -parameter "UseWebDavP"] == 0 } {
+    if {![fs::webdav_p]} {
         return "ho"
     }
     if {$package_id eq ""} {
Index: openacs-4/packages/file-storage/www/index.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/file-storage/www/index.tcl,v
diff -u -N -r1.35.2.1 -r1.35.2.2
--- openacs-4/packages/file-storage/www/index.tcl	1 Feb 2021 11:05:42 -0000	1.35.2.1
+++ openacs-4/packages/file-storage/www/index.tcl	19 Apr 2021 13:01:13 -0000	1.35.2.2
@@ -102,7 +102,7 @@
     set up_name [lang::util::localize $up_name]
 }
 
-set use_webdav_p  [parameter::get -parameter "UseWebDavP"]
+set use_webdav_p  [fs::webdav_p]
 
 if { $use_webdav_p == 1} { 
     set webdav_url [fs::webdav_url -item_id $folder_id]