A40 and CF (?) errors

[maumari]

Hi, one week ago I've got a Powershot A40 and a 256 mb Hamlet CF. Very satisfied with quality, features and usability, compared to the price.
After a wedding reportage and two days of family shooting I downloaded (not deleted) the 150+ images via a USB CF reader and everything was ok. Once I put back the CF into the A40, in browsing mode (9 thumbnails) I noticed some blank thumbnails (5 out of 150+) with a "question mark" into them ("JPEG format not valid").
I couldn't see the corresponding images on the camera, but I could read them via CF reader. However I deleted them (blank thumbnails) from the camera.
I continued shooting for two days, but suddenly the camera begun to have difficulty on power on (i.e. U can push the on/off button but sometimes it goes on, sometimes it doesn't).
Last night I tried the original CF (8mb) and everything worked fine for a couple of times (the camera turned on and off, took pictures, deleted them...). I put back the 256 CF and the camera switched on saying "CF card full". I formatted the 256CF with the camera, turned off and on again, took some pictures, and so on... I thought I resolved! Go to bed.
This morning I tried to turn the camera on with the 256CF and after several tries, it turned on saying "CF empty".
Before sending back camera and CF, I wonder if anyone has some suggestion other than "an exorcist"....

Thanks in advance

[Conk]

Try putting in a smaller card. Then try another 256 meg card if a smaller one works out. If the problem persists then return the camera. However, I have never heard of such problems with the A40. These are just a few suggestions. Also try e-mailing Canon and see what their response is.

[maumari]

Thanks for the suggestions, Conk.
I tried another 256mb CF of the same maker, it works fine. And yesterday I used the original 8mb from Canon with no problems.
I'm returning my 256mb CF to the shop, they will change it with a new CF card.
I'm happy it was not the camera broken...