The PST files must not be in use at the time of migration, so make sure that users do not have them open. You may find that it is better to copy PST files so that users can continue using the original files while you migrate the contents of the copies.
The Vault Service account must have Full Control access to the PST file.
The Storage service for the destination vault store must be running.
PST Migrator's automatic correlation rejects any PST file that has more than one user account with write permission, leaving you to do the correlation manually. You may find it easier to set the permissions appropriately before running PST Migrator.
PST Migrator does not migrate PST files that are password protected. You must remove such protection before running PST Migrator.
Items can be assigned a specific retention category during PST migration. You may want such items to retain this retention category if they are moved later to a folder with a different retention category. To prevent Enterprise Vault from changing the retention category, ensure that the policy option, is not selected. This option is on the tab of the Exchange mailbox policy properties.
If PST files are scattered in different locations on users' disks, you may find it easier to move them all to a central location before you run PST Migrator.
If you have PST files that must be migrated to different vault stores, the quickest way to sort them is probably to use the automatic correlation within PST Migrator and remove those that do not correlate.
If you intend to use the automatic PST compaction feature at the end of migrations, you may need some spare disk capacity to provide room for the compaction to take place. You could need as much as the size of the largest PST file, plus approximately 5% of its size.
PST Migrator checks the mailbox storage limit when a mailbox has either Prohibit Send or Prohibit Send & Receive mailbox limits set. If both these limits are set, PST Migrator does not migrate items that would exceed the lower limit. If only one of the limits is set, then PST Migrator obeys that limit.
If a PST file fails migration because the mailbox is full, you can modify the appropriate mailbox storage limit and then migrate the PST file again.
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