VCenter 6.7: Resizing disk fails with an error message.

My VCenter recently failed to resize a disk with error “Invalid operation for device ‘0’”. Here’s how I solved it.

VEEAM failed recently to backup one of your servers. The error message was “Error: Virtual disk size is not a multiple of 1KB.”.

For future references: I was using a VCenter 6.7 Version 6.7.0.30000 with the HTML5 interface.

To solve that issue, I had to use the flex (Flash) client and everything worked perfectly without any error.