"Unable to open ..." error when trying to open the presentation in BrightAuthor, but the same presentation opens without the problems on another computer

BrightAuthor presentation files (.bpf files) created on one computer may fail to be opened on another computer due to a language issue (i.e. the language that the operating system is set to). Follow the steps on this page to fix the problem: http://support.microsoft.com/kb/942460/en-us

Verify the operating systems on both computers are set to the same language, change the language to English temporarily, then try to open the presentation file in BrightAuthor.


You attempt to cast a numeric string to a numeric data type, using code similar to the following.

Dim strInput As String = "10"
Dim intResult As Integer = 0
intResult = Convert.ToInt16(strInput)
Catch ex As Exception
MessageBox.Show("Error: " & ex.Message)
End Try


You receive a System.FormatException with the following error and stack trace.

"Input string was not in a correct format."

A first chance exception of type 'System.FormatException' occurred in mscorlib.dll
at System.Number.StringToNumber(String str, NumberStyles options, NumberBuffer& number, NumberFormatInfo info, Boolean parseDecimal)
at System.Number.ParseInt32(String s, NumberStyles style, NumberFormatInfo info)
at System.Int16.Parse(String s, NumberStyles style, NumberFormatInfo info)
at System.Convert.ToInt16(String value)
at TypeConversionTest.Form1.cmdConvert_Click(Object sender, EventArgs e) in C:\Source\TypeConversionTest\TypeConversionTest\Form1.vb:line 7


There is an incorrect value in the following value in the Windows registry:

HKEY_CURRENT_USER\Control Panel\International\sPositiveSign

This value should be empty for most English Language settings. Note that when this error occurs, the value may appear empty visually, but may contain a space or unprintable character.


While it is possible to directly edit the value for the problem key, the preferred method is to change the Regional Settings to a different Region/Language and then reset it to the desired setting:

1. Open the Regional and Language Options applet from the Control Panel.
2. Note the Current Format.
3. Change the Current Format to "English (Australian)".
4. Click Apply.
5. Change the Current Format to the desired format (for example, "English (American)").
6. Click Apply and then click OK.

This action resets every value under the HKEY_CURRENT_USER\Control Panel\International registry key.

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  • 0
    Eric Fauque


    I've just experience this problem with one of my clients.

    I live in Montreal, Canada, in the province of Quebec.

    Around 8 million people living in Quebec, over 7 million speaking French.

    The OS on the laptop I use to program  in BrightAuthor is in English and most of my clients use there computers in French.

    So, when I exported a presentation from my laptop to my clients PC, and tried to open it,  I got a message saying Unable to open...

    I did the language change from French to English on my clients PC and it worked when in English, but not when I set it back to French.

    Can't you fix this problem for good in the next BrightAuthor update?

    Having to ask clients to switch language settings on there PC every time they use BrightAuthor makes no sens!


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