Hello Subhi,

> procedure AlterUser(Action: TIB_AlterUserAction; AUserName,
> AUserPass, AGroupName, AFirstName, AMiddleName, ALastName: string);

> I got the error message "Access violation at address 00000000. Read
> of address 00000000". How to solve this?

You have a nil pointer somewhere. Three possible causes are:

1) You didn't initialize a certain variable. You should be able to
discover which one by stepping through your code in the debugger.
Look at which line the error occurs and examine the objects /
properties / pointers that are accessed on that line.

2) A compilation error that shows up at runtime. I don't know if this
happens often with Delphi, but with C++ Builder I sometimes get the
same error as you, even when my code is 100% correct and there are
no nil pointers around. After deleting all intermediate files and
rebuilding (without changing anything in the source), the error
disappears.

3) An error within the IBO code? The AlterUser functions have always
worked for me, but maybe there have been modifications - maybe
something to do with the user management changes in Firebird 2.


Greetings,
Paul Vinkenoog