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Outlook Express Troubleshooting

An error occurred while the spelling was being checked


When explicitly trying to check the spelling of an e-mail using Outlook Express the following error is displayed:

An error occurred while the spelling was being checked

also, when sending the e-mail the following message is displayed:

The spell check on this document was halted. Do you want to send anyway?

Possible Causes and Remedies:

  • This error can occur if the registry key HKEY_LOCAL_MACHINE\Software\Microsoft\Shared Tools\SharedFilesDir has a missing backslash.
    1. Using regedit navigate to:

      HKEY_LOCAL_MACHINE\Software\Microsoft\Shared Tools

    2. The value for 'SharedFilesDir' should have a trailing back slash. If this is missing then add it. Typically the value for 'SharedFilesDir' is:

      C:\Program Files\Common Files\Microsoft Shared\

      Apparently this can prevent "Csapi3t1.dll" from being located and hence the spell check fails.

  • The directory indicated by "SharedFilesDir" (see point above) should contain a directory called "Proof", this should contain (amongst others) the files Csapi3t1.dll and either Mssp232.dll or Mssp2_en.lex. See the Microsoft Knowledge base article Q224176.
  • A little old but for an excellent article on this problem see
  • Some of the registry keys used in the process may contain short versions of the path. Even if these are correct it may break the process.
    1. Using REGEDIT navigate to:

      HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Shared Tools\Proofing Tools\Spelling

    2. Under here these will be one or more four digit keys. Each of these digits indicates a possible locale for which the system has been configured. To identify which locale is applicable for you, look up the (decimal) number up in the Windows Locale Table.

      Common values are:

      1033: English (United States)
      2057: English (United Kingdom)

    3. Navigate to

      HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Shared Tools\Proofing Tools\Spelling\NNNN\Normal

      where "NNNN" is the appropriate four digit (decimal) locale value.

    4. Under here look at the values for "Dictionary" and "Engine". If either of these are defined using the shortened form of directory specifier, e.g.

      Dictionary = C:\PROGRA~1\COMMON~1\MICROS~1\Proof\MSSP2_EN.LEX

      Then replace this with the long form, e.g.

      Dictionary = C:\Program Files\Common Files\Microsoft Shared\Proof\MSSP2_EN.LEX

      Repeat this for 'Engine' also.

      This can cure the problem even if the shortened form of the path is correct.

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