As Voyager pointed out above, you can change that opening message to anything you want... it has no bearing on the functionality of the scanner.
It is an often commented on situation when folks see something on that screen that wasn't there before, or is different than what was expected and they don't realize it was something they may have done that changed it.
When writing to the scanner, what ever text is in the "opening message" box from the "display options" tab in the Profile Editor at that time will show up on the opening screen when the scanner is booted.
If you have a 436 and have customized that opening screen in the profile editor and set up your favorites lists, and then wish to load those same favorites lists to a 536.... the opening message that you had set for the 436 will now show on your 536 as well as your favorites lists etc. - it's all part of the profile.
If you have a 536 and have it set in Sentinel to show a certain message, and then you "read from" a 436 to that same profile in Sentinel, your 536 message will be overwritten with the message that was in the 436. When you write to your 536, the message that was in the 436 will now show on your 536 opening screen.
In reference to ofd8001's post above..... there was a version of Sentinel that had the incorrect spelling of "Barecat" as the default "opening message" for the default profile when you downloaded the software. New scanners had the correct spelling of "Bearcat" loaded in them as the opening message from the factory. As soon as you wrote to the scanner with anything you changed in Sentinel, the incorrect spelling in Sentinel overwrote the correct spelling in the scanner. It surprised a lot of people as to how it happened.
Setting what you want for text in that "opening message" box, and then "writing" to the scanner will definitely change it.
In the VERY rare instance that it refuses to change by doing that, your SD card has become corrupted. The "opening message" text is stored in the "profile.cfg" file in the top level of the SD card and it is read by the scanner when it boots. A corrupted card can prevent that info from being overwritten by Sentinel with your changes. The OP may actually be experiencing that problem if he is unable to change the message.
If you have 2 or more of those scanners and want a different message to show on each of them, using separate profiles for them will keep each with it's own message.
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