What Does Error Code C=343 Mean?

According to Intuit, Error Code C=343 can occur when:

  • you’re not running the latest release of QuickBooks
  • 1 of 2 Microsoft Core XML Services .dll files is unregistered, missing, or damaged

Confirm you’re running the latest release of QuickBooks.  To verify your QuickBooks release, from within QuickBooks press F2 to display the Product Information window.  The Product shows both your version and release in the upper left corner.

If the problem persists, either MSXML3.DLL or MSXML4.DLL is unregistered, missing, or damaged.  The first troubleshooting step is to re-register both of these files while QuickBooks is not running and then re-start QuickBooks to see if the problem has been resolved.  If the error recurs, you’ll need to download and re-install Microsoft’s Core XML services.

See our related article on another error involving Microsoft’s XML Parser, an unrecoverable error has occurred exception msxml could not cocreate instance.

For more information on the troubleshooting steps to resolve Error Code C=343, consult this Intuit knowledge base article.

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  1. I am also getting this error:

    Unexpected Error
    An error has occurred in QuickBooks.

    Please restart QuickBooks and try again. If you
    continue to experience this error, please note the
    C= value and contact technical support.

    C = 343

    I am trying to delete an account that is not used – no information shows up when I do a quickreport (all date range).

    I have tried all of the above suggestions, but this does not resolve the problem.

    I have also tried on different computers.

    The weird thing is, I can delete other accounts, just not this one. I have also tried rebuilding the company file – no go.

    If anyone has any ideas – please let us know.

    • Sam – If you’ve tried all of the steps listed in this article, there are just a few more things you can try. 1) Resort your QuickBooks lists; 2) Determine (if you can) whether the account you are trying to delete is a QuickBooks special account type; that can be more difficult without special tools; you can determine an account’s special account type (if any) by creating some test transactions and see where they end up; 3) Rebuild your company file 2X in succession (yes, that’s rebuild, then rebuild again), then save it as a portable file, then create a new company file from that portable file; 4) Export your account list to a .csv file and look for oddities; consider changing the name of the account in question to something shorter, or removing any characters other than basic letters and numbers; sometimes elements in the account name itself are the source of the problem; and lastly 5) change the name of the company file; QuickBooks has restrictions on the name of the company file, and we’ve seen these produce unexpected results; if you’ve violated a restriction, it could have an impact here. Those steps would not be the first things to try, but you’ve done the primary recommendations, so now we’re reaching a little further afield to try to solve it.

      Let us know how things work out.