So i got the message when i selected a bunch of folders from the hfs tree to remove them all at once:
Access violation at address 004CB434 in module 'hfs.exe'. Read of address 00000004
HFS 2.3 beta (221)
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Stack list, generated 07-02-2009 10:37:02
[004CB434]{hfs.exe } ComCtrls.TTreeNode.GetTreeView (Line 7080, "ComCtrls.pas" + 1) + $3
[00477618]{hfs.exe } Controls.TWinControl.DefaultHandler (Line 7273, "Controls.pas" + 23) + $28
[004CB414]{hfs.exe } ComCtrls.TTreeNode.GetHandle (Line 7075, "ComCtrls.pas" + 1) + $3
[004CBF01]{hfs.exe } ComCtrls.TTreeNode.GetParent (Line 7458, "ComCtrls.pas" + 2) + $3
[0054CC8E]{hfs.exe } main.setNilChildrenFrom (Line 6615, "main.pas" + 3) + $6
[0054CE09]{hfs.exe } main.TmainFrm.remove (Line 6654, "main.pas" + 27) + $5
[0054CED9]{hfs.exe } main.TmainFrm.Remove1Click (Line 6665, "main.pas" + 2) + $13
[00465A51]{hfs.exe } Menus.TMenuItem.Click (Line 1878, "Menus.pas" + 14) + $C
[0046726D]{hfs.exe } Menus.TMenu.DispatchCommand (Line 2603, "Menus.pas" + 5) + $5
[0046865C]{hfs.exe } Menus.TPopupList.WndProc (Line 3393, "Menus.pas" + 4) + $12
[0041E486]{hfs.exe } Classes.TThreadList.UnlockList (Line 3359, "classes.pas" + 1) + $7
[0043F804]{hfs.exe } Graphics.FreeMemoryContexts (Line 5032, "Graphics.pas" + 12) + $5
[00468599]{hfs.exe } Menus.TPopupList.MainWndProc (Line 3374, "Menus.pas" + 2) + $8
[0042AC08]{hfs.exe } Classes.StdWndProc (Line 11572, "classes.pas" + 8) + $0
[0046C47C]{hfs.exe } Controls.FindControl (Line 2103, "Controls.pas" + 6) + $C
[00494E1E]{hfs.exe } Forms.TApplication.ProcessMessage (Line 7670, "Forms.pas" + 23) + $4
[00494E63]{hfs.exe } Forms.TApplication.HandleMessage (Line 7689, "Forms.pas" + 1) + $6
[004950FE]{hfs.exe } Forms.TApplication.Run (Line 7773, "Forms.pas" + 16) + $3
[0056C94E]{hfs.exe } hfs.hfs (Line 99, "" + 22) + $2
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System : Windows XP Professional, Version: 5.1, Build: A28, "Service Pack 3"
Processor: Intel, Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz, 2380 MHz MMX
Display : 1280x768 pixels, 32 bpp
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Product Versions
hfs.exe: Build: 0 04-02-2009 3:35:56