The following bug has been logged online:

Bug reference: 1613
Logged by:
Email address: hyperspacez (AT) yahoo (DOT) com
PostgreSQL version: 8.0.2
Operating system: Windows XP
Description: Installation flaw
Details:

Hello,
I am a new user of PostgreSQL. However, when I went to install it on my
Windows XP machine, it was running fine until I ran into the screen where it
asks me for my account name, password, and whether to run as service or not.
When I entered a simple password, it (the installer) said I was using a
possibly insecure password, and asked me if I want to use a randomly chosen
when. When I clicked 'Yes', it showed me the randomly generated password
which was horrendously long. When I clicked the 'back' button on the
installer so that I could change it back to my original one, and then
clicked 'Next' after retyping my original password, it gave me this error:
Account Error: "Invalid username specified. Logon failure: unknown user name
or bad password" - It somehow set a flag saying the password is set (for the
installer!!!), and I didn't write down the long and abstract randomly
generated one, so now I can't install it because I get this error over and
over. If I change the account name or the service name, I get this error:
Account Error: "Internal account lookup failure: No mapping between account
names and security IDs was done" and am still unable to install PostegreSQL
even though I hadn't installed a file from the actual installer. Might you
know how to unset the password flag from the installer? I tried cleaning my
registry and re-extracting postgre from the archive to no avail. Thanks.

P.S. I tried the manual as well.
-Jake.

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The installer will reset all its information if you restart it (unless
you completed the install in which case some information is retained. To
lose all there, uninstall the product).

To solve your problem, though, I think you just need to delete the
account and start over. Since it hasn't been used yet, you should lose
nothing by diong that.

//Magnus

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