FIX: FoxPro Crashes in FOXHELP.DBF "Error Messages" Topic

The information in this article applies to:

• Microsoft FoxPro for Macintosh, versions 2.5b, 2.5c

SYMPTOMS

FoxPro for Macintosh crashes with a "Type 1" error when you are scrolling down the "Error Messages" Help topic in the .DBF-style Help file (FOXHELP.DBF).

CAUSE

The memo field in the FOXHELP.DBF file for the "Error Messages" record is corrupted.

RESOLUTION

To avoid this problem, use FoxPro's graphical Help file, FOXHELP.HLP. If the Macintosh does not have enough memory to run the graphical Help file while FoxPro is running, see "Additional Alternatives" in the "More Information" section below.

A listing of error messages can also be found in Appendix B (pages 441-483) of the "Developer's Guide."

STATUS

Microsoft has confirmed this to be a problem in the Microsoft products listed at the beginning of this article. This problem was corrected in Visual FoxPro 3.0b for Macintosh.

MORE INFORMATION

Additional Alternatives

Systems that only have 8 megabytes (MB) of memory or less may not be able to display the FoxPro graphical Help file while FoxPro is running. This is documented in the FoxPro Readme file that can be found in the FoxPro folder. In these cases, there are three possible alternatives.

• Delete the corruption from the FOXHELP.DBF Help file. This will keep FoxPro from crashing when the "Error Messages" topic is chosen and scrolled through. However, there will not be complete help information on error messages. The procedure to do this is below.

  1. In the Command window, type the following commands:

        SET HELP OFF   && Just in case foxhelp.dbf is the current help file
        USE SYS(2004)+"FOXHELP.DBF"
        GO 24          && The Error Messages topic should be record # 24
        MODIFY MEMO details
  
        There should be information on error messages in the memo field. If
        not, browse the database and find the record that has "Error
        Messages" in the topic field. Double-click the details memo field.
  
     2. Scroll down the details memo field. After the "Area cannot contain
        handle. (1011)" error, there will be rows and columns of "hollow box
        characters" if the font is set to Geneva. If the memo field is
        displayed in FoxFont, FoxPro will crash when you are scrolling down
        to the point indicated above. The font can be changed with the Font
        command on the Text menu. Delete from the beginning of these
        characters to the end of the memo field.
  
     3. Press CTRL+W to close and save the memo field changes.
  
     4. Close the FOXHELP.DBF file and issue the following command:
  
           SET HELP TO SYS(2004)+"foxhelp.dbf"
  
     -or-
  
  

• You can run the graphical Help file when FoxPro is not running. The obvious disadvantage here is that you will have to close FoxPro before looking in Help for error messages. The procedure for running graphical Help while not in FoxPro is below.

  1. Double-click the FoxPro Help application found in the System

        Folder:Extensions:Microsoft:Help folder.
  

  2. From the File menu, choose Open. Note that there should only be

        Apple, File, and Edit menus when you are in FoxPro Help.
  

  3. Open the FOXHELP.HLP file found in the FoxPro folder. For ease of

        use, you can place a copy of the FOXHELP.HLP file in the Help folder
        along with the FoxPro Help application.
  

  -or-

• Remove FoxFont from the fonts installed in the System Folder. The disadvantage of this option is that .DBF-style Help will not display properly and FoxPro for MS-DOS applications will not be able to be run on the Macintosh unless they are transported. For more information, see "Part 4: Installing Fonts" in the FoxPro Readme file.

Steps to Reproduce Problem

1. Make sure that all information and files are saved because this procedure will crash FoxPro. It will normally not crash the Macintosh, but to be safe, save any unsaved files in other programs that may be running.

2. Make sure the FoxFont font from the FoxPro Fonts installation disk is installed. Your Macintosh may not crash if this font is not installed. "Part 4: Installing Fonts" in the FoxPro Readme file, found in the FoxPro folder, states that FoxFont is required in order to run .DBF- style Help. .DBF-style Help will start up without FoxFont; however, it will not be formatted correctly and extended (special) characters will probably be displayed, depending on which font the Macintosh uses in place of FoxFont.

3. Type the following commands in the FoxPro Command window. Press ENTER or RETURN after each command:

         SET HELP TO SYS(2004)+"FOXHELP.DBF"
         SET HELP ON
         HELP
   

4. Double-click the "Error Messages" topic (located in the listing of General Topics).

5. Use the scroll bar on the right side of the help screen to scroll down through the error message information. Eventually FoxPro will quit with the following error message:

         The application 'unknown' has unexpectedly quit, because an error
         of type 1 occurred.
   

   The Macintosh may lock up without an error message. This behavior has been observed on a Centris 610. Some Macintoshes may not quit or lock up.

   In any case, the memo field will not contain usable information after a point.

REFERENCES

"Language Reference," version 2.5, pages 737-739 "Developer's Guide," version 2.5, page 441-483 "User's Guide," version 2.5, pages 151-155 FoxPro Readme file, found in the FoxPro folder or on Disk - 1 Setup of the FoxPro installation disks