*QUESTION:
Is it possible to have the width fixed on Cognos report excel export?


*ANSWER:
No, it is not supported.

About 30% of the formatting functions available in IBM Cognos Business Intelligence are not supported in the Microsoft Excel spreadsheet software.
In particular, Excel does not allow changing locale-dependent formatting attributes, such as the following:

Decimal Separator
Exponential Symbol
Group Separator
Monetary Decimal Separator
AM String
Day Name
Day Short Name
Decimal Delimiter Symbol
Month Name
Month Short Name
PM String


In addition, Excel does not support the following:

Format Width
International Currency Symbol
List Separator
Percent Symbol (Excel does not support percent symbols for charts)
Multiplier
Overline Text Format
PerMill Symbol
Plus Sign
Scale (Excel has a different scaling formula than IBM Cognos BI)
Calendar (Excel does not allow changing the calendar)
Era Name
First Day Of Week
Show Era