Hi all I need a major upgrade setting on my newest application. I had read related document. I have some question. If I have version1 and version2 application, and version2 need adopt major upgrade setting in Installshield in order to uninstall version1 completely. I know the first step is to generate new "product code". But when I want to follow document to right-click "Add Major Upgrade Item" in "Upgrade Windows Installer Setups" treenode, I found another item named "ISPreventDowngrade" exists. "ISPreventDowngrade" seems to be the same as Major Upgrade Item I added....Should I add Major Upgrade Item that exist with "ISPreventDowngrade"? If it does, why? Is it possible that "Upgrade Windows Installer Setups" have many item?
A given installation package can have multiple major upgrade items. This allows upgrading several product lines (upgrade codes) into a single line, as well as other detailed cases like the ugprade prevention. Note that unlike the usual upgrade item, the upgrade prevention one checks for versions after yours instead of before yours, and does not remove ones that are found.
