Upgrading database to 1.5.4 - zc_install doesn't recognize admin password

[dbltoe]

It's normally just a matter of overthinking what it's asking. If you import a database and the system needs a username and password to update it, wouldn't it be looking for the username and password for the database you imported?
The good news is that the new install for 1.5.5 makes it a little clearer as to what is needed.

[acmaurer]

It's normally just a matter of overthinking what it's asking. If you import a database and the system needs a username and password to update it, wouldn't it be looking for the username and password for the database you imported?
The good news is that the new install for 1.5.5 makes it a little clearer as to what is needed.

Guilty as charged! Sometimes the best thing to do is take a break and come back to it later.

After several attempts in which I went through the whole upgrade process and the installer wiped out the database (meanwhile I entered new admin creds), it finally recognized the 1.3.9h database. I found the upgrade option, but was myself stuck on the new admin creds I had entered in previous attempts.

Then, when it finally completed I got stuck with the sessions problem documented in another thread: the admin login page wouldn't take those admin creds to log in to the admin area. Took a while to figure that one out, but trying with another browser (as suggested by Dr. Byte) proved the issue and closing out and reopening Firefox made it work again.

All of which leads me to heartily endorse the advice given here (best practice, really): always, always, always practice the migration on a clean copy of your data in a new and separate location. Work out all the bugs before you even think of touching production!

Thanks again to all who took the time to respond.