property MsgBox.Image(Style as OutStyle) as Variant
Specifies the image being displayed for a specified style.

TypeDescription
Style as OutStyle A OutStyle expression that indicates the predefined image being changed. Only exCritical, exQuestion, exExclamation or exInformation are accepted. 
Variant A Picture object that indicates the image's picture. ( A Picture object implements IPicture interface ), a string expression that indicates the path to the image file being loaded, a string expression that indicates the base64 encoded string that holds a picture object. Use the eximages tool to save your picture as base64 encoded format.
Use the Image property to assign a new image to exInformation, exQuestion, exCritical or exExclamation predefined styles. Use the Button property to assign new captions for predefined buttons.

By default, the following images are loaded:

The following sample changes the default image for exInformation style:

With MsgBox1
    
    Dim s As String
    s = "gBHJJGHA5MKAAEIe4AAAFh0ODYFCA7AolLYFGBljBwAo7QoFIqbApQUoFLa7kzFApllRwlrQAp7mB7bYFQs1SE1TblAqleAQIpwCBlXYQODQCE3CCQcobMqwDZ7YobSDQqjbDabrCweAlHZFEpwWAlQrFsjQEs7GAwHdrKFst5FLYwLaFjKlGB7XYwQrQGCQYt/bYwTd+UrlHdSjy7jzQHdcHa7eFyOBFMp7oKboKwIqFzllzrQIqQXejbchYshbZQKCFKBw1xwSGtWBQwG2aBQrRQyRbLZw3yQ3ybLZ74iFUpbqvKbZbwvO5ql6LlLbFeBlMpw7CQ7CbMqQWHfYplrRlUrQ8zbp7lonX6xwOB7+Cl2SwOGFOHSOC7csueA9uNABSwAWA9vPAxtj2WEEskmR9kKQpNwgUsIFgzxykg8EMl28BoNJDDrJyfZNk2UsSF2Tb+K0fZSlKWEWl3FxilKXZtlKYpyukfZYFgYsemgWBoHgXZdmhIshm3IZyn2YpimhJptmLJLrH2aErSsbZoHKeEtH2bcvy+csvngbclnLM8znhNU1n3Np9gDOE4zlOc6TrO07zxPM9T3Pk+z9P9AUDQVB0JQtDTihgABCfICAChh/gAFlEoTSggARSB/gSDgkFgUBgkGBAJhULhkFgUJhkOCARg0OgiAiKZTEWDAZjUbhkFiEYjCYEAhkEJgqFQMgkh8CQplUNhsFQcoSkeGAxj0CgUlkSAQCCSQXEMSg6HmcxlE+FQNhKJR6CkUw"
    s = s + "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"
    s = s + "AaRUjlEEAQCYeAgBDA2G0EAoh2CyDuLQGIBQGgTCINsAICwsAMCkGsLwSQchSHSLYbYvh1DtCmGQUItgpBaA6BweIyBcjoFMKsFwuhKP4GSLoeApgNiIDMF4UA+hrGAEiFYTAaRxCuGOMQAwrA4gBGQMAAgFw2CwGCDEDorBYDCAwLQYwRQphvEyDgbgvg5AkFOBwO43RGixGMMahw7A4jHBiH0Fg8hjgtDwAcYIDxHBIEEKAYgLB/iFA8BwdQNRiDED+AEXwJwhARBwOcVgcxnAxHaOwGYzgajLFuAIQIWh5DVBkHEF4rwUBzAGEwG47R6DTCgEcFo9RqBUCmD0GggR7gWCaJ4YgCwbAoGiA0BYhAWj2GwGQS9awQgwEyK0ew2grgTG6GcSwWgRidFENIH4JRwDkG6HgZ4qBgiUEcJgf4+hbBeDiHMRI5BSgEBAGAO43gYBqGgMQEAaQbDuDwCQPIfh6h3GsJ4OISRzivAIB0GwRxyDXE8DoXInxAAKEUDkIIdxLBuG0HEVApxXB6HUAwWw3g9CKFgMcBwuxIi0GuG4fY7RADmFcPsdwgRHDuH2O8YABwXg8HMFIeQ7QkCiGQCcb46B5CMCUOoHgrBhgDEKHUc4tgTBFEkKcHooXJiiBcFEV4KwmhLAqAgKQqAfBtH+FAVI3gth5BWFMbAYhRBICeNATYjwID6HSEMBg/gmirDUNQdQqx5AbBoGsfo9hVgJH8NQW4KwghABKA8fo+xjqQGQJEJwdRiheF4C"
    s = s + "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"
    s = s + "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"
    s = s + "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"
    s = s + "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"
    s = s + "sAzgYAsA6ATAEgdhKAshLBcArg+hKhEhggBgdhPB8BEg1gZAwhrgxBDBOh6gsBDgQhFBwBSg3gtB6hFBfhRgchZAcBFhaCChbB0Adg5gwANBchUBFhdhsAThegcAdBMAShGBUB7AbhihEAchjhEBGBkh8ATBlh8AVhPg6gdBRAqhGhSB6gPAdBTgKgdhVBahGhaBpgtBWgCgCBzgKhHBxAcBHByGoBzA8BHB0AUAKk4AAAdiAg=="
    
    .Image(exInformation) = s
    
    .Out "We have changed the default image for exInformation style.", OutStyle.exInformation, "exInformation style"
End With

The following screen shot shows the same message without changing the default image of the exInformation style: