The migration process migrates the contents of PST files to archives. If the PST files then continue to have more items stored in them, you need to perform further migrations to archive new items.
If you try to migrate thousands of PST files at the same time, the migration can take a long time to run. The time taken is comparable to the amount of time your Enterprise Vault system would take to archive the same amount of data from mailboxes. We recommend that you experiment with a few PST files and gradually increase the numbers with which you work.
Table: Feature comparison of PST migration tools
Note the following:
All PST migration tools skip PST files if the vault store that contains the corresponding archive is in backup mode.
Classes of items that are not eligible for archiving are ignored when you migrate PST files into Enterprise Vault. You can use the tab in the Exchange PST Migration policy to define the classes of items that will be archived when the policy is applied. You can use the tab in Directory properties to edit the list of message classes that appear in policies.
Enterprise Vault ignores items that were created on a computer that uses a language that is incompatible with that of the Storage service computer. For example, if a PST file contains both Japanese and English items, and the Storage service computer uses Japanese, then the English items are ineligible for archiving. Contact Symantec Corporation if you want to migrate PST files that contain such items.
If you are importing archived items that have previously been exported by Enterprise Vault, then you may need to deal with unknown retention categories.
In the Exchange mailbox policy you can configure Enterprise Vault to change the retention category of items when they are moved within an archive. 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.
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