DigitalVolcano Software Support

What is difference between. Is changed MD5 to CRC32 for duplicate identify?

Thank you

Any 'lettered' versions, (a,b,c) will not have had the core program changed. They are usually installer or language pack changes (1.4.7c had support for many more languages added the installer only)
There should be no need to download one of these updates if you already have 1.4.7 installed.

Also Duplicate Cleaner has not used CRC32 for hashing since v1.3.2 - MD5 is much more reliable.