Can't tell...
I can't tell from the description what caused the issue to be honest.
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Previously, the plan intend is to used server migration, as such, the PST was deleted (files found) and search for this PST by locator task has been unchcked, thus client driven migration was excuted.
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Doing that will not make client driven migration happen. The only way for client driven migration to happen is for the client to be enabled for client driven migration via the VAC. Simply unselected a file for migration on the server, which the PST locator task found, doesn't send EV down the client driven migration path.
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So, I asusme the configuration for desktop policy is the same for enabled client driven policy.
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There is a section in the PST policy for "Post Migration", you'll see that some things relate ONLY to client driven migration. One of those is to make the PST hidden etc.
Hope that helps,
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