OK I had an awful problem replacing my stock SD card with my new 16GB one. I had rooted and installed a version of LeeDroid with A2SD+ will with the stock SD in the phone. Many people had posted "how" to do it but using their methods it didn't work. Below I will detail the method I used to get it working (trial and error, leaving out the errors!) As you may or may not know A2SD+ requires an ext partition on the SD card, this is a linux file partition and cannot be seen by a windows computer. If you insert a SD card into the phone without this partition the phone will cycle in a bootloop. You will need ROM manager and Titanium Backup for this process. 1. If you do not have access to a linux computer, download a live CD. I used ubuntu 10.10. 2. Run the live CD and insert your sd card. Open the disk utility, unmount all partitions and then format the disk using to the master boot (whatever it's called). This first formation option is at the top of the disk utility page. 3. now click on the "bar" of memory shown (picture of the unallocated space). Now below this you will see "create partition". Click this and change the entire disk to FAT. 4. exit out of the live cd and restart in windows. 5. now on your phone (still with old SD card in it) make a Titanium Backup of all your apps and data. I didn't need to use mine but it's just incase something goes wrong. 6. now open ROM manager and make a Nandroid backup. This is like an image of your phone as it currently stands. 7. in windows, copy the contents of your SD card to a folder on your PC. 8. download a new ROM that doesn't use A2SD+.. (I downloaded the LeeDroid non A2SD+ version) and place it in the root directory of your SD card 9. Open up ROM manager, install rom from sd, clear data and wipe cache. Make some tea as this will take about 10-15 minutes usually. It will restart in your no non A2SD ROM. 10. Turn off your phone, insert the NEW SD.. power up and install ROM manager from the market. 11. Open ROM manager, and select the first option (flash clockworkmod recovery, or something similar. this will download the update.zip to your SD) Now select to partition the SD card the same way the old one was (512MB ext, 0MB swap usually). Leave the phone until it starts up again. 12. Now go to the folder on the PC where you backed up the old SD card, file the folder "clockworkmod" and copy it to the new SD. 13. Open up ROM manager and restore the backup you made at the start. When your phone starts up, it will be as it was before, with a larger SD Any problems / questions please ask.