The use of these aliases cannot be disabled, however, the retention period (30 days of inactivity after last user session) can be changed in the registry. It is controlled by the value HKEY_LOCAL_MACHINE\SOFTWARE\Veeam\Veeam ONE Monitor\Service\InactiveLocalUserKeepIntervalSec (DWORD), which equals 2592000 seconds (30 days) by default.
Note that 0 value means that these users will not be deleted (no retention period), so for the immediate removal, the value must be set to 1 second.
To match the actual users and their temporary account aliases, Veeam ONE uses the "Veeam_<USER5><1A3B5C7D>" format , where "<USER5>" contains five first letters of the username used for authentication, and "<1A3B5C7D>" is a hash-code based on the username and password.
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