There are several factors to consider when an X2 card fails to upload photos. It's important to note that the only way files are automatically transferred from an Eyefi X2 card is wirelessly. It does not matter what kind of device the card is plugged into; if the card is getting power, it will attempt to transfer files. We recommend the following steps if you're having trouble transferring photos from your Eyefi X2 card.
Does the card recognize there are transfers pending?
You may need to make sure the images that have not yet transferred are in a supported folder. If you have turned on the Selective Transfer option, make sure you are write protecting your photos on the Eyefi card. If you are transferring RAW files, have you configured the Desktop app to receive RAW files?
Make sure the card has power
If you're having difficulty transferring files from your Eyefi X2 card, make sure that your camera's power-management settings are adjusted so it does not power down immediately. Most cameras have the ability to adjust the amount of time before the camera cuts power to the card slot. Make sure to extend the amount of time the camera remains on to as long as possible via your camera's "Auto Power Off" setting. This will ensure that the card has power when it needs to transfer files.
Enable Wireless Transfers in Camera
Certain Eyefi Connected cameras disable the wireless functionality of your Eyefi card by default, which will prevent your Eyefi card from wirelessly transferring photos and videos. If your Eyefi Connected camera is failing to transfer photos, check to see if the Eyefi functionality of your card has been disabled. For Canon cameras, follow the instructions in Enable Wireless Transfers in Canon Cameras for more details. For Nikon cameras, follow the instructions in Enable Wireless Transfers in Nikon Cameras for more details.
Can the card connect to your smartphone or tablet?
When an Eyefi X2 card is powered on in a camera it will attempt to transfer files to the smartphone or tablet it's paired with. It is important to be sure that your smartphone or tablet recognizes your Eyefi X2 card. If you are unable to add the Eyefi Mobi card as a network, then it is unlikely photos will transfer. If you are using an iOS device, be sure to select the Eyefi Card in the Apple Settings, under WiFi.
When encountering wireless transfer failures from within your camera, move your camera closer to your smartphone or tablet. Take several JPG photos and wait for a minute or two to see if the card transfers the new photos.