SDHC card won't mount on iMac

[bonefish]

I've been using Panasonic SDHC 16Gb cards for months now and just over the past 2 days they haven't been mounting on my desktop using my SD slot. They are mounting on my laptop, however. I ran an update on the iMac thinking that maybe that would help, but it hasn't. To mount the card I need to restart the machine with the SDHC card inserted. This is the only way I can see it. Any suggestions? I DL'd an application that converts Mpeg2 files to .mov, but have since deleted it. Could that have been the cause? As I said it's been deleted out of my applications and I ran an update, but no luck. Any suggestions? Thanks.

 

[Xaveryptak]

I've been using Panasonic SDHC 16Gb cards for months now and just over the past 2 days they haven't been mounting on my desktop using my SD slot. They are mounting on my laptop, however.

I have similar problem with my PC's internal multicard/USB reader. It suddenly stop seeing any cards but USB ports still work. Rebooting with cards inserted doesn't solve the problem. I've been googling the problem but can't find any solutions.