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Fix Failed to loadAutoResponder rules from ... AutoResponder.xml - Unclosed literal string


Frequently, with a large (360MB FARX) autoresponder set, when Fiddler is forced to shut down unexpectedly, I get the following message (screenshot attached)

Failed to load AutoResponder rules from C:\Path\To\AutoResponder.xml. There is an unclosed literal string.

I have to re-import the rules from an exported FARX file whenever this happens to be sure I have all the rules in place.


Suggested steps to reproduce

* Create an autoresponder rule set of approximately 350Mb in size, and 500 rules.

* Terminate Fiddler unexpectedly.

* Relaunch Fiddler.

This should be made more robust because when you're trying to run Fiddler on machine startup unattended this error dialog prevents Fiddler from functioning. 

  • Guest
  • Apr 29 2016
  • Needs review
  • Attach files
  • Eric Lawrence commented
    June 18, 2016 00:49

    If you're running Fiddler unattended (which isn't really supported) you definitely should be using the -quiet flag.

  • Guest commented
    July 02, 2016 00:48

    It's fairly close to being robust enough to run unattended. If there were just a few (massive) bugs like this ironed out it would be.

    I believe I launched it without the -quiet flag in this case to diagnose the issue.

  • Guest commented
    July 23, 2016 00:22

    Any updates on this?

  • Guest commented
    August 23, 2016 03:09

    And @Eric Lawrence - running with -quiet, are you saying this error message would have gone away? I'm skeptical; it's a critical error. And if not, I'm assuming it would not have magically loaded a repaired AutoResponder.xml file.  

  • Guest commented
    August 25, 2016 04:51

    Something as simple as an option to synch the AutoResponder rules to disk every x minutes would be a workaround. If the rules don't properly save on exit - use the last saved one. That beats a malformed XML representation of the rules any time. 

  • Eric Lawrence commented
    August 25, 2016 05:51

    > "when Fiddler is forced to shut down unexpectedly"

    Can you elaborate on that? Is crashing Fiddler part of a routine workflow somehow?

    Fiddler's AutoResponder is configured to read the .farx file in read-only mode, and it only writes the file upon shutdown. It shouldn't be possible for Fiddler itself to corrupt the file when killed, only the OS should be in any position to do so. Auto-saving the file on a timer is more likely to result in corruption, and would have a major performance impact when the file is so large; generally speaking, the design of the AutoResponder was such that it was presumed that large response files would be referenced from filesystem locations instead of stored within the FARX itself.

    Do you have an example of a broken file we could look at?

  • Guest commented
    August 28, 2016 21:55

    Yes, when it happens again I will absolutely send the file

    Just to clarify - It is AutoResponder.xml that it claimed was unreadable - not the FARX