Upload troubleshooting (Windows)
If you're unable to upload photos, please follow the troubleshooting steps below. Picasa relies on your Internet Options in Control Panel (Wininet) to connect to the Internet. Some browsers, such as Firefox, do not use these settings. It's possible that your Internet connection through a different browser works just fine, yet Picasa still can't connect. If one of these steps solves the problem, you don't need to complete the remaining steps.
Windows: STEPS
Upload troubleshooting (Mac)
The screenshots looks like they were taken on a Mac computer if so here are some information and solutions that might help:
From the iPhoto Library
Picasa for Mac has been designed to play nicely with iPhoto.
Picasa doesn't store any of your photos. It simply scans your hard drive and displays the photo files it finds. In this way, Picasa folders represent the actual directories containing photos on your computer's hard drive.
Picasa handles the iPhoto Library in the same way, with a small variation made for the way in which the iPhoto Library organizes your photos: If you've made edits in iPhoto, each album or event in your iPhoto Library contains an 'Originals' folder and a 'Modified' folder. Picasa scans the photos and videos in both the 'Originals' and 'Modified' folders, and displays a single collective folder with the most recent version of each file.
The photos in your iPhoto Library will be displayed in Picasa in the 'iPhoto Library' collection as read-only files. The read-only status is necessary to ensure that Picasa and iPhoto work well together. You can do a lot with read-only files in Picasa -- upload, create a collage, create a movie, email, print -- but you won't be able to make any material changes: this includes editing, moving, deleting, adding tags and using Sync to Web.
Of course there's a solution: When you attempt to use Picasa to edit an iPhoto Library picture, Picasa will ask your permission to copy the entire folder containing that photo to a location outside of the iPhoto Library -- they're placed in a different folder under 'Pictures' titled 'Imported from iPhoto.' You'll then have access to the full range of tools that Picasa offers. It's also possible to import your entire iPhoto Library in this manner. Just go to the File menu > Import from iPhoto... Please be aware that this action will make copies of your entire iPhoto Library.
By default, Picasa for Mac will look for your iPhoto Library in its usual location (Pictures > iPhoto Library); other iPhoto Libraries will be excluded from Picasa. If you'd like to remove the read-only 'iPhoto Library' from Picasa, you can do so using the folder manager.
Mac uploader errors
If you haven't signed the Terms of Service, you might see an error when trying to connect to Picasa Web Albums with the Mac uploader. You may be able to resolve this issue by visiting http://picasaweb.google.com and agreeing to the Terms of Service. After doing so, try signing in again. If the issue hasn't been resolved, check that your browser is not set to block all cookies.
Although many of these troubleshooting steps may apply to Mac users, they're built out specific to Windows. Mac users, please visit the Picasa for Mac Help Forum for troubleshooting assistance. There you'll find help from Google Guides and our most knowledgable users.
If you're unable to upload photos, please follow the troubleshooting steps below. It's possible that your Internet connection through a different browser works just fine, yet Picasa still can't connect. If one of these steps solves the problem, you don't need to complete the remaining steps.
The latest version of our software contains fixes for many issues that our users have reported. Please upgrade to the latest version at http://picasa.google.com/ to see if that resolves your issue.
Clearing your cache and cookies can help resolve uploading issues. Follow these instructions to clear your cache and cookies.
Signing out, clearing your cache and cookies, agreeing to the Terms of Service and signing in on Picasa again fill fix the issue.
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