By default, when you slice a view into Microsoft Excel from IBM® Cognos® TM1®, the workbook contains a workbook level named variable, TM1RebuildOption, that is set to 1 by default. This causes the worksheets in the book to be rebuilt on opening (which forces a recalculation to happen on each sheet in the book). This action is necessary if the sheets contain Active Forms. If you are not working with Active Forms, you may not want all workbooks to use this default behavior.
All worksheets recalculate when a Cognos TM1 workbook is opened. The workbook was created by slicing from Cognos TM1 Perspectives and contains the workbook level named variable TM1RebuildOption = 1.
By default, as of Cognos TM1 9.4.1 all new books created by slicing have a workbook level named variable TM1RebuildOption=1 in them. This makes the workbook rebuild on open, causing a recalculation of all sheets, which is important for Active Forms but may not be the desired behavior if you are primarily working with non-Active Form worksheets.
To prevent sheets from using the default to always rebuild when slicing, change TM1RebuildDefault from T to F (or add TM1RebuildDefault=F if it doesn't already exist) in your tm1p.ini file. When TM1RebuildDefault=F the books get the workbook level named variable set to TM1RebuildOption=0 on slicing. This is equivalent to how Cognos TM1 worked prior to the introduction of Active Forms.
If this option is set to T or doesn't exist, slicing from a view in Cognos TM1 Perspectives sets the TM1RebuildOption workbook level named variable to 1 which forces a rebuild on open. If this option is F, the name variable TM1RebuildOption is set to 0, which does not rebuild. For a particular report, for example, an Active Form, you can set the name variable to 1 instead of the default 0.
By default, a new install does not have the TM1RebuildDefault parameter at all which provides the default behavior of slicing with TM1RebuildOption=1.