Seems odd that it happened when you disconnected the headphone - that shouldn't make any difference to how the phone performs.

I'm assuming that the SD cards you're using aren't fake and work at full capacity, as that could be a possibility as to why you're getting the message.

Also make sure you unmount the SD card in Settings > Storage when the phone is on when you're removing the card.

Some SD cards aren't as easy to (re-)format as others - they can seem more fussy about what you do with them. In which case the default reformatting tools on your PC may not be adequate. There are a number of freeware tools like SD Formatter and Gnome Partition Editor (more complicated to use), which should do the job if it's a formatting issue.

 

If the problem is the same with the other two SD cards and you're sure they're all reliable (not fakes), then we can discount that it's the SD cards at fault. (When formatting SD cards remember they should be formatted in FAT32.)

There is a possible fix using fastboot commands. It resets the diagnostic monitor on your phone which could be stopping your phone from recognising SD cards. You'll need to download SDK Tools to run ADB commands to your phone via your PC. To read a little more about this, and how to set it up, go here where you'll also find a link to download SDK Tools to your PC (or go here for the official SDK Tool download).

Once you've set up your PC and connected it to your phone via the USB cable, enter Fastboot on your phone: With your phone off, press and hold the volume button down and press the power button. Select Fastboot via the power button.

Then via ADB on you PC enter the following commands:

fastboot oem enableqxdm 0
fastboot reboot

If successful, on reboot, your phone should recognise your SD card.

Finally, you could try a factory reset - you'll lose all your personal data if you do this, so make sure you have it backed-up.

NB The last character of the command line 'fastboot oem enableqxdm 0' is a zero.

 

I can't think of much else to recommend. You could try the fastboot commands again. Some people have reported it works after they've done it a few times.

You also have the option of doing a factory reset.

You could explore rooting your phone and flashing custom ROMs - that should exhaust all your options regarding finding a software solution to your problem.

If neither of these works, then, unfortunately, I think you're looking at a hardware issue.

 

1. Rooting and flashing ROMs are two separate things.

You can just root your phone and not bother with flashing a custom ROM. Rooting your phone allows you to fully exploit the phone once you have turned its security off (S-Off), enabling apps to access and write to areas of your existing ROM that wouldn't be available with the security on (S-On), e.g. like enabling full/complete back-up of everything, processor clocking and system tweaks, accurate 3G/wifi monitoring, new fonts, enhanced power saving mods, etc.

There are already custom ICS ROMs for the Desire S based on the ICS ROMs that have been officially released by HTC, however, these (custom ROMs) are in beta at the moment.

If your phone is S-Off and you try to update the ROM by OTA (Over The Air) then you'll most likely brick your phone. Sometimes this can be fixed, depending on the current ROM, the ROM you want to return to and how you S-Off/rooted your phone. But the advice is to never accept an OTA on an S-Off phone.

You may be interested to know that HTC's official ICS update for the Desire S will come with Sense 4.0, which will remove the 3D look and feel of Sense 3.0, reverting back to something similar to the simpler look and feel of Sense 2.1. If your phone has a stock HTC ROM (not a carrier/branded ROM), then you might want to wait a few weeks as HTC have said they'll release the ICS update for the Desire S this month (April). HTC stock ROMs will get this update first, depending on where you are in the world.

2. You need to turn the phone's ROM security off in order to get root. Without S-Off you won't be able to root - it's a necessary part of the process. S-Off lifts the default read/write restrictions on your phone, allowing you complete access to it.

3. Think of SuperUser as just another name for being rooted. It allows you and any app complete access to your phone.

Yes, it's possible to revert back to unrooted and S-On - but this is where some people have problems depending on what their original ROM was and how they achieved S-Off. It's highly recommended to read as much as you can about rooting, flashing and backing-up before you embark on getting S-off, root, etc.

Unfortunately, as your phone's SD card functionality is not working, the Goldcard is not an option for you, as it requires an SD card.

 

I'm not certain if it will solve your problem, but it's the only thing I can think of that you haven't tried that could work.

Once you have S-off and root, you can then flash another ROM to your phone. Technically, if you can find it, it could be the same version ROM/RUU as you have now, or an earlier one, or one of many custom ROMs.

When you flash a different ROM over your existing ROM (phone's software), you can overwrite the operating system, radio and kernel (core operating system) with any that you like, which a factory reset doesn't do as it's just 're-copying' itself to your phone. Flashing a different operating system and/or kernel than your existing OS and kernel will definitely prove if you have a hardware or software issue.

I recommend you read this post from FoX777 on rooting the Desire S, in the 'All things root' sub forum. It should cover the basics and will give you a few helpful links. If you require further advice re rooting, you can start a new thread in that sub-forum.

To see some of the latest custom ROMs and what they offer, go here, over at xda-developers.com.

 

I had a similiar issue on my Mytouch 4G. "SD empty or unformatted", something along those lines anyways.
My wife has the same phone. I loaded my SD card into her phone. It gave an error message for almost 2 minutes, then it beeped and the messages all went away. The storage info said it was mounted. I put it back into my phone and it works fine. It must of been stuck in a weird state that her phone was able to recover and mine couldnt.
Hope it helps