The link in the first post takes me to the free download page which subsequently gives the following downloads for the 8700:

8700
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Handheld Software 4.1.0.224
Handheld Software 4.1.0.286


Handheld Software 4.1 User Guide 8700.pdf
SIZE: 1 MB
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Can anyone tell me where the OS 4.2.1.rel180 can be found?

thx