Problem with Calculate

I have a workbook with half a dozen worksheets, where some calculations are done after its respective macro has ran. In the end, the purpose is to present a briefing in a worksheet once a change has been done. This change should be updated in the other worksheets, in order to do the calculations.
The problem is that sometimes, once the change has been done, I can't get to update all the worksheets, even using Calculate. Is this an Excel bug?
And... after closing an reopening Excel, everything works fine again.

what does the macro do during calculation? does it "paste values" or inserts formula

for example if cell A1 = 2 and cell B1 = 2 in sheet1 and you want to show the sum in cell C1 then what does the macro do?

Range("C1").Value = Range("A1").Value + Range("B1").Value

or

Range("C1").Value = "=" & Range("A1").Value & "+" & Range("B1").Value

Also

How are you generating the Summary(briefing)... using macros or using formulas?

It sounds like you have a timing issue where some sheets are dependant upon other sheets already being updated. If so then some other solution may be in order.

Basically, there are 4 sheets. One contains a vector of values whcich are modified by the user. then, the vector is refered in the other 3 sheets with something like =Vector!A2, then in every one of these sheets there are diferent operations within diferent elements of the vector. These operations are aritmethic operations with the INDEX function.
After one element of the vector is changed, it is then updated in the othe sheets and then I run a marco which identifies specific kinds of changes.
The problem is that suddenly, the calculation stop, and even pressing F9 it won't work. It does until I access a single cell and press enter....

Can you see if its possible that there may be a circular reference or some other circular chain of events that are firing between workbooks/sheets?

I checked for circular references and other possible problems, but I found none. In fact, the three sheets where calculations are done, were originaly three independent workbooks, they only take the values of the vector in the main sheet.
What surprises me is that suddenly Excel won't work anymore and even if there is an evident change for a value, an update won't occur pressing F9 but only if the cell is activated and the you press enter.