I've put macro in module, then make a custom button on the toolbar to invoke
a macro.(according to excel help):

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Create a toolbar button that runs your macro

1. On the Tools menu, click Customize, and then click the
Commands tab.

2. Under Categories, click Macros.

3. Drag the custom button to the toolbar where you want it.

4. On the Customize dialog box, click Modify Selection,
and then click Assign Macro.

5. In the Assign Macro dialog box, click the name of your
macro, and then click OK.

6. To change the appearance of the button, click Modify
Selection again, point to Change Button Image, and click one of the
available images; or click Edit Button Image and use the Button Editor to
create your own image.

7. Click Close.
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But something was wrong when I've assigned macro, and I find that this
custom Toolbar button appers in all my Excel documents.

When I click on it, it show that workbook contains macros, though there was
no macro earlier. I find that this button attach "Module1" macro to Excel
file when I click on it. So, all Excel document now have this nasty button,
that insert macro in workbook.

How to remove this Toolbar Button from all Excel documents? How to remove
this unwanted macro from workbooks where this module has been already
inserted?

Thanks