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acrobatithit-webdav-server

Issues with Adobe Acrobat

We have some users who are using Adobe Acrobat to edit .pdf files over WebDAV. There are a couple of issues that we are experiencing.

  1. The acrobat client seems to be very chatty. We get multiple PROPFIND calls before the first GET. To edit even the simplest pdf takes ~11 secs. due to all these calls which includes PROPFINDS & OPTIONS, a LOCK, GET, PUT, UNLOCK and frequently a pair of MOVE/DELETE commands.
  2. When the user eventually saves then closes the document and immediately reopens the document, their changes to not appear to have saved. If they wait for about 30 seconds (possibly less) before they reopen the document the changes do show up so there appears to be some type of caching going on, but our website (asp.net) has output caching turned off.
  3. Sometimes the users get an error of 109 saying the document could not be saved. This appears to be coming from Adobe Acrobat because we don't see errors in the log, however it could be related to #1 above where the MOVE/DELETE has been issued and enough time has not passed.

My questions are therefore

  • Have you tested/used Acrobat for editing pdfs?
  • If so did you have these issues?
  • Is there a setting in the WebDAV engine that allows you to turn caching off or does it use the underlying IIS settings?
Solution

  • I guess you are using Microsoft Mini-redirector driver (Windows Shell, WebDAV client provided with Windows) to open and edit documents.

    1. This is a Mini-redirector specifics, sometimes it traverses folders and submits other unnecessary requests.

      Regarding performance. This may be caused by proxy settings. Please see "Long Delays When Connecting and Browsing WebDAV Server" section here.

    2. This is typically caused by Mini-redirector cache. As far as I know there is no any documentation about how to disable cache in Mini-redirector. There is no real solution for this, you just need to wait for some time until the client cache invalidates.

      The server Engine itself does not have any caching options. It just processes the WebDAV request and generates response. It also independent of hosting environment and its settings, such as IIS, HttpListener, etc.

    3. Please examine the WebDAV log file WebDAVLog.txt. By default it is located in \App_Data\WebDAV\Logs. Are there any exceptions in it?