Sony SEL90M28G Manual page 7

The camera does not recognize the lens and
an error message is displayed.
The camera does not recognize the lens and an error message is displayed.
This solution applies to both of the following error messages:

Check the Lens attachment.

No Lens Attached.
Follow the steps below to troubleshoot this issue. If model-specific information is required to
complete any of the steps in this solution, refer to the operating instructions supplied with the
product.
1. Make sure you are using a compatible lens.
To check the list of compatible lenses for your camera, refer to the following link:
Camera Body-Lens Compatibility Information
IMPORTANT: If attaching the camera body to an astronomical telescope or other
similar device, (depending on your camera) it will be necessary to do one of the
following:
o Set the mode dial to Manual (M).
o
Set the Release w/oLens option in the camera menu to Enable.
o Set the Shutter lock option in the camera menu to Off: no lens.
NOTE: Some Lensbaby lenses may attach to the camera body. However, Lensbaby
lenses do not communicate electronically with the camera body and cannot be
recognized. Sony does not support the use of Lensbaby lenses.
2. Check if the lens is connected properly.
NOTE: If the lens is not attached properly, the connection points that enable
communication between the camera body and lens do not make contact. Do not push the
lens release button, but turn the lens clockwise and attach to the camera body until it
clicks. Below is an example of the lens release button location.