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No error dialog message when creating a file with a character '?' in its name

Anonymous
2025-04-29T10:44:14+00:00

When I create a file with name having a character '?' in the file name. Neither a file is created, nor I see any error message from Windows. But when I do the same with other invalid characters like ':', I see a dialog as below

Windows for home | Windows 11 | Files, folders, and storage

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  1. Ramesh Srinivasan 81,155 Reputation points Independent Advisor
    2025-04-29T11:29:04+00:00

    Hi Muhammad,

    The reserved characters, "?" and "*", are also wildcards. Hence, you can type the File Open or Save as dialog boxes to list files in a folder via the common dialog. However, you can't save files with such reserved characters in the file name.

    Please see:

    Naming Files, Paths, and Namespaces - Win32 apps | Microsoft Learn:

    https://learn.microsoft.com/en-us/windows/win32...

    Excerpt:

    *******

    Do not use the following reserved names for the name of a file:

    CON, PRN, AUX, NUL, COM1, COM2, COM3, COM4, COM5, COM6, COM7, COM8, COM9, COM¹, COM², COM³, LPT1, LPT2, LPT3, LPT4, LPT5, LPT6, LPT7, LPT8, LPT9, LPT¹, LPT², and LPT³.

    *******

    and

    *******

    The following reserved characters:

    < (less than)

    > (greater than)

    : (colon)

    " (double quote)

    / (forward slash)

    \ (backslash)

    | (vertical bar or pipe)

    ? (question mark)

    * (asterisk)

    *******

    Maybe you're not getting the "file name is not valid" message is because "?" and "*" are wildcards.

    MS-DOS and Windows Wildcard Characters | Microsoft Learn:

    https://learn.microsoft.com/en-us/previous-vers...

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  1. Ramesh 176.2K Reputation points Volunteer Moderator
    2025-04-30T14:08:32+00:00

    Now I understand, thank you for explaining.

    You're welcome, Muhammad.

    Regards,

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  2. Anonymous
    2025-04-30T06:56:02+00:00

    Now I understand, thank you for explaining.

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  3. Ramesh Srinivasan 81,155 Reputation points Independent Advisor
    2025-04-30T06:38:46+00:00

    Hi Muhammad,

    You don’t see the same error for ? and * is because they are wildcards. The other reserved characters I mentioned are not wildcards.

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  4. Anonymous
    2025-04-30T04:15:05+00:00

    Thank you for replying,

    Yes, I understand.

    let me rephrase my question, why the behavior is not consistent? I see an error dialog when the name has ':' but not in case when there is a character '?'.

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