A quick search turned up this link:
https://support.google.com/picasa/answer/156342?hl=enPicasa & Picasa Web Albums are no longer supported.
Learn moreWhat's happening to Picasa?
Picasa is now retired. (If you speak English, you can
read the blog post herePicasa Web Albums
If you have photos or videos in a Picasa Web Album today, the easiest way to still access, modify and share most of that content is to log in to Google Photos, and all your photos and videos will already be there. Using Google Photos, you can continue to upload and organize your memories, as well as enjoy other great benefits like better ways to search and share your images.
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I am guessing you already saw that. Somewhere in that mess I saw you need to have your user number not your user name AND you have to get through:
One account. All of Google.
Sign in with your Google Account