anything is changeable in RPT, if it's black and white (not flagged as a dataset candidate or substituted from a reference) just type in the new one
Best practice for passwords is to have them in a dataset, then substitute from the dataset
Then once working the dataset can be encrypted.
Here's a blog posting I wrote that will sub a password from a dataset and can be applied to multiple tests
http://www.testworkbench-community.com/blogs/changing-a-hard-coded-password-in-multiple-tests-in-performance-tester
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