Excel may not update external links when opening a WB

[AmicusA]

Hi,
When I open, by macro, WB1, despite the fact that the WB to which links of WB1 are pointing is open itself, Excel pretends not to be able to update the links.
When I choose to modify the links, and I select the linked WB, everything is ok.
How may I prevent that problem?
Kind regards
AmicusA

[AmicusA]

Ok,
I think having found the solution: I haved saved the ".xls" destination file as ".xlsm" and since it works!
Regards