This doesn’t seem to be a very common problem, but if it happens to you it can be very annoying!
Sometimes, when trying to upload an image to a WordPress post or page, you may get an error message that says, “Are you sure you want to do this? Please try again”.
If you click on the “Please try again” link you just get taken back to the main dashboard, but within the pop-up box where you would usually choose your image.
The most likely cause for this is an incompatible plug-in.
To find which one and correct this problem, first … did you recently upload or update a particular plug-in just before you starting seeing this error? If so, deactivate that plug-in and then try to upload an image again. If you can now upload images again, that plug-in was causing the problem.
However if you’re not sure which plug-in is at fault, deactivate all of your plug-ins. Now try to upload an image and you should find it uploads just fine.
So now go back to your plug-ins page and activate one plug-in. Try uploading an image again. Did it work?
If yes, that’s great. Now activate a second plug-in, then try uploading an image again.
Keep going through this process until all of your plug-ins that you want activated are active, except for at least one that, when activated again, will cause that image upload error. When you find that plug-in, either delete it or leave it deactivated.
You may find it helpful to have two tabs open in your web browser – one on the plug-ins page and another on a draft post/page where you can test uploading images.
I hope this fixes your images upload issue. 🙂