FX is referred to as “Fast Transfer”. Internally properties are kept raw formats and dynamically converted to meet the specification of the requester. Using Fast Transfer, the properties of a message can be copied in their raw format without translation. This object represents a source stream when copying properties.
Open Item Limits Open item limits are limits placed on the number of items that can be opened by a single mailbox in a single session. However, a user can have multiple sessions opened simultaneously. For example, if a user has two sessions opened, the user could open 1,000 folders. If you want to modify these limits, see "Configure Open Item Limits" immediately following the table.
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