I use both pMachine Pro and Wordpress for blogging. pMachine Pro is a really handy little program; basically you just put PHP includes in your existing site to use it.

But it’s kind of twitchy sometimes. Occasionally it will refuse my password and I’ll have to change it. Here is the process I use to do that - kind of simplistic, but this is applicable to any simple login process when trying to recover a password.
Start phpMyAdmin or whatever MySQL frontend you’re using from your hosting control panel. At the opening screen, select the database for your pMachine install. From the list of tables, select pm_members. This should present a table structure and a selection of tabbed options.

Select the Browse tab. This will display a query field and a list of users.

Click on the small pencil (edit) icon next to the user ID entry you wish to edit. This will display a table for the record showing the fields and their current values. Note that only the password hash is displayed, not the plain text.

In the function column for the pass field, select PASSWORD from the drop down box. You may then delete the hash and enter a plaintext password in the corresponding value field. Letters in this field should be all lowercase. Make sure the box at the lower left says ’save’ and click on the GO button.
You will be returned to the previous screen which will display the SQL query you just created. The hash displayed opposite the user ID you selected should have changed (unless you used the exact same password). Exit phpMyAdmin and login to pMachine with your username and new password.