Ага, на 2000 есть такая бага.

MSDNACC97: Keyboard Does Not Respond When TreeView Control Has Focus
SYMPTOMS
You are unable to type data into a text box or combo box on a tab control that contains a TreeView control on another page. However, you are able to set the value of the text box or combo box with a macro or with Visual Basic for Applications code. This behavior only applies where the TreeView control is on a sub-form and that sub-form is on the Tab control.

NOTE: In addition to the TreeView control, the symptoms discussed in this article have also been reported for the ListView ActiveX control.
CAUSE
The TreeView control has the focus.
RESOLUTION
If possible, in Design view, place the TreeView control directly onto the Tab control page. If the TreeView control must be on a subform, move the focus by clicking a control on the page that contains the TreeView control, or close and reopen the form.
STATUS
Microsoft has confirmed this to be a problem in Microsoft Access 97.

MSDN
ACC2000: The Keyboard Does Not Respond When an ActiveX Control Has Focus
This article was previously published under Q210608
Moderate: Requires basic macro, coding, and interoperability skills.

This article applies to a Microsoft Access database (.mdb) and to a Microsoft Access project (.adp).


SYMPTOMS
You are unable to type data into a text box or combo box on a tab control that contains a Microsoft TreeView or ListView ActiveX control on another page.

This behavior occurs when all of the following conditions are true:


The Microsoft TreeView or ListView ActiveX control is on a subform.
The subform is on a tab control.
The subform is on a different page of the tab control than the one with the text box or combo box.
You clicked the TreeView ActiveX control to give it focus before switching pages on the tab control.
NOTE: You can set the value of the text box or combo box with a macro or with Visual Basic for Applications code.
CAUSE
The Microsoft TreeView or ListView ActiveX control still has the focus. Even though another page on the tab control has been selected, and you have clicked the text box or combo box control, the ActiveX control retains focus.
RESOLUTION
To work around this problem, use any of the following methods.
Method 1
Place the Microsoft TreeView or ListView ActiveX control directly onto the tab control, instead of placing it onto a subform first.
Method 2
If the TreeView or ListView ActiveX control must be on a subform, remove the focus by clicking another non-ActiveX control on the same page as the TreeView or ListView ActiveX control.
Method 3
Close and reopen the form, and then go directly to the text box or combo box that you want without clicking on the TreeView or ListView ActiveX control.
STATUS
Microsoft has confirmed that this is a problem in Microsoft Access 2000.