Originally posted by Zephos All I did was tap the rings around the glass loose with a screw-driver and a hammer, then unscrewed the glass. That's it. Had nothing to do with the contacts. I did, however, hot glue some black fabric inside to prevent reflection, but I have a hard time imagining how that could cause what seems to be an electrical problem. The fabric is not touching or near the contacts. Some of the springy contacts though are protruding less than others.
Maybe you accidentally dropped some hot glue in a spot where is not suppose to be!?
Is not conductive... so it should not make a big difference, unless is wedging against something!?
The contacts should be more or less at the same level. If one is higher considerably than the other something might be wrong... how hard did you knock the ring? Is there a chance you might of hit something by mistake while you were doing that? Can you show a picture of the difference between the contacts?
If this teleconverter was working without issues in the past and started miss-behave after you removed the glass, something must of been knocked off by mistake. Have you tested the convertor when it had the glass?
Edit
Also, as "Not a Number" is asking... what battery are you using? I remember having a similar issue with the pop-up flash because of battery problem - nothing to do with a teleconverter... even though you said without the teleconverter everything is OK... but then it must be the teleconverter... starting to scratch my head now.