DOCUMENT:Q216480 11-JAN-2001 [vbwin] TITLE :PRB: Error Setting Default Value of Optional Byte Arg to TRUE PRODUCT :Microsoft Visual Basic for Windows PROD/VER:WINDOWS:5.0,6.0 OPER/SYS: KEYWORDS:kbVBp kbVBp500bug kbVBp600bug kbGrpDSVB kbDSupport ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Visual Basic Learning Edition for Windows, versions 5.0, 6.0 - Microsoft Visual Basic Professional Edition for Windows, versions 5.0, 6.0 - Microsoft Visual Basic Enterprise Edition for Windows, versions 5.0, 6.0 ------------------------------------------------------------------------------- SYMPTOMS ======== Setting the default value of an Optional Byte argument to TRUE causes the following error when the project is compiled with Binary Compatibility: in the class module has arguments and/or a return type that is incompatible with a similar declaration in the version-compatible component RESOLUTION ========== Use 255 instead of TRUE for the default value. MORE INFORMATION ================ Steps to Reproduce Behavior --------------------------- 1. Create a new ActiveX DLL project. 2. Insert the following code into Class1: Option Explicit Public Function meth1(pf1 As String, Optional pf2 As Byte = True) As Boolean ' Sample method End Function 3. From the File menu, select Make Project1.DLL. 4. From the Project menu, select Project1 Properties. 5. Click on the Component tab. 6. Set the Version Compatibility to Binary Compatibility. 7. Verify that Project1.dll is listed in the File Location box at the bottom of the form. 8. Close the Project Properties dialog box. 9. Select Make Project1.dll from the File menu. Change the path to the DLL so that it is in a different location than the originally-compiled version of project1.dll and click OK. The error occurs at this point. REFERENCES ========== For additional information about a similar problem with optional String argument default value, please click the article number below to view it in the Microsoft Knowledge Base: Q176164 FIX: Optional Argument Default Value Breaks Binary Compatibility Additional query words: ====================================================================== Keywords : kbVBp kbVBp500bug kbVBp600bug kbGrpDSVB kbDSupport Technology : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVB600Search kbVBA500 kbVBA600 kbVB500 kbVB600 Version : WINDOWS:5.0,6.0 Issue type : kbprb ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2001.