Cant merge two partitions

Simple questions, I have an external Hard Drive with 3 partitions however I want to merge two of them together to make 2 overall. Im using Computer Management and clicking extend volume, However it gives me the error - 'The operation you selected will convert the basic discs to dynamic disks...' I click yes, And it claims not to be supported meaning I still have 3 partitions.

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Trying to merge the Unallocated middle section with the Backup on the right, With no success.


I'm running Vista if thats helps.

Any help?

If thats the only 2 options, Then im inventing a 3rd option. Keep the 3 partitions and make do with them.

Cheers.

I managed to just merge all the partitions together, And im just using the disk as a whole. Much easier really. Means I dont have a set limit for either music or backup now.