Picasa displays some video formats by default, but for most formats you need to install external codecs.
Or, the videos might be shown, but without sound or in bad quality. You may get an error message when trying to play a video: "This movie failed to load"
See video file types supported by Picasa here: Files supported by Picasa
When you import from a camera or card, the videos may not be seen by Picasa or imported via Picasa's import screen if the proper codec is not installed. After the codec is installed, it may be necessary to import the videos again if they were not correctly imported. Other import option to try: Import using Windows Explorer according to the "Method B" directions here: Import photos and videos
Enable movies in Picasa
Go to Tools menu, then Options > File Types tab. At the bottom of the file types display list are two boxes:
"Movies (.AVI, .MPG, .ASF, .WMV)"
"QuickTime Movies (.MOV)"
Make sure "Movies" is check marked.
For Windows users, "Quicktime Movies" will be grayed out if Apple's Quicktime codec is not installed.
Exit Picasa and restart it to see if the desired video format now works.
If the Movies and QuickTime Movie settings were grayed out or if importing still doesn't work, the next thing to try is to install or reinstall your video codecs:
(Re)install codecs
Download and install the latest version of K-Lite Codec Pack from: http://www.filehippo.com/download_klite_codec_pack/
Use the green button in the upper right-hand corner that says "Download Latest Version (xx.xx MB)"
More info at the Codec Guide website: http://www.codecguide.com/download_kl.htm
When you install it, use "Normal" mode unless you are more experienced. Read every screen carefully as there may be a couple of screens asking if you want to install other programs such as Video Adblock and others. You can "decline" these.
After installing the codecs, "Enable movies in Picasa" again (Tools > Options > File Types) and select the video types, if necessary.
K-Lite Codec Pack will enable .MP4 videos to be displayed in Picasa, but provides no support for .MOV videos. See below . . .
To update K-Lite Codec Pack after it is installed
Type "Codec Tweak Tool" in your Windows Start menu
When found, click it
Click "Yes" to the User Account Control warning
Under "General" look for "KLCP update check" and click it. The program will check for updates and let you know if any are available. You can also schedule updates in the KLCP Update Check window
Click "Close" when finished with the update window
Click "Exit" to close Codec Tweak Tool
.MOV and .MP4 files
When Apple's QuickTime for Windows codec is not installed on your computer, .MOV files (Apple Quick Time Movies) will not be displayed in Picasa3 nor in the Import function. In Picasa's Tools > Options > File Types tab, "Quicktime Movies (.MOV)" will be grayed out.
To play .MOV files in Picasa, we previously recommended installing Apple's QuickTime for Windows. However, QuickTime for Windows is no longer supported by Apple, and warnings were issued in April 2016 by the US Department of Homeland Security to uninstall it immediately. See the following: here, here, here and here
We also recommended installing a light version of Quicktime - the QT-Lite alternative. However, due to security issues, we can't recommend that program either. It was discontinued in 2010. Use at your own risk! See VLC Media Player below!
If you have a lot of Quicktime (.MOV) videos in your collection you will really need to have a Quicktime codec installed to Import them and manage them in Picasa. Of the 2 choices above QT-Lite is probably the best alternative because it only installs the Quicktime codec, not a working version of the Quicktime player. Not having the player makes it less likely the codec will be called outside of Picasa. For best safety practices, don't import or play .MOV videos from unknown sources, and of course make sure your Antivirus software is up to date. To install QT-Lite:
Download QT-Lite
Start the QT-Lite installer.
In the "Select Components screen, Uncheck the 2 Plugin options leaving only the Components with a black square.
On the next screen, uncheck Enable MP3 Support.
After QT-Lite is installed go back to Tools menu -> Options -> File Types, and enable Quicktime (.MOV) Support.
The good news is there are alternatives and you can view .MOV and .MP4 files by using other free programs (here are two that we recommend):
VLC Media Player http://www.videolan.org. Using VLC, you can view .MOV and .MP4 files and much more.
VLC Media Player plays .MOV and .MP4 videos by double clicking those files in Windows Explorer. If double-clicking doesn't open the movie, you'll need to set it up by following directions here
Windows Movie Maker (included in the Windows Essentials 2012 program suite): http://windows.microsoft.com/en-us/windows/get-movie-maker-download. Windows Movie Maker can view and edit .MOV, .MP4, .AVI files and more.
Drag files from Windows Explorer into Windows Movie Maker.
A Codec (Coder-Decoder) is an external library that helps Picasa and other programs decode and display formats that are not displayed natively. A prime example was the Quicktime video format such as the .MOV that was developed by Apple. The Picasa user needed to install the Apple Quicktime codec in order to play .MOV videos in non-Apple computers. As mentioned above, we can no longer recommend installing Apple's QuickTime for Windows computers.