There are two main cloning methods/options:
- Software based
- Hardware based
Both have their PROs and CONs.
Software based ones can encounter more issues due to their requirements (they actually analyze the source drive and filesystem as well as the condition of the drive itself)
So, software based cloning can give and error or fail due to a software as well as a hardware problem.
Hardware based cloning would not care about any software issue, malware infection, partition size or disk fragmentation. As long as the hard drive itself is in good condition, it does the sector-by-sector copying just fine. The health of the Source and Target drive are the most important two factors.
If the target drive was partitioned and formatted previously by the user, the sector size might be the only concern as most cloning devices might have a limitation of accepting only specific size sectors such as 512 bytes and 4,096 bytes (you would have to check its manual).
If the target drive is brand new and not formatted (typically they are not), then you are good to go.
Hardware based cloning might be more ideal for most home users as the same hardware is used for cloning typically doubles as a USB Docking station to access any supported hard drive as an external storage.
Now, to answer your question: No cloning method is 100% guaranteed to work post operation!
Ultimately, you have to remove the old one and connect the new one and plug in the power cord and fire it up to test.
Here is an example of an inexpensive USB 3 based cloning device that costs less than $30.
PROs of Hardware cloning:
- Either works or doesn't. If the process completed 100%, it should work just the same way as the old drive worked but presumably faster if it is a faster drive
- No configuration or adjustment necessary, as long as the Target (New) drive is same size or larger, it is as simple as pushing the button on the dock to clone a drive (no computer is even necessary!)
- Inexpensive
- Also works as a docking station to use with supported drives so it can be used as an external storage media
CONs of hardware cloning:
- Typically slower, larger the drive the longer it is likely to take
- No way to adjust the partition sizes during the operation (to adjust the partition sizes, a 3rd party software is needed)
What I would recommend doing all these prior to using any type of cloning:
- Disable/deactive and hibernation/sleep mode
- Make sure there is no malware infection
- Run CheckDisk to fix filesystem, crosslinked files and mark/fix bad/weak sectors
- After running CheckDisk (aka ScanDisk), analyze the drive fragmentation to make sure it is less than 3%, if not defrag the (source/old) drive
Important: NEVER boot the computer with both the source and the newly cloned target drive connected in the same computer. Both drives would be bootable and identical in every way including the SID#, so it is a big NO-NO.
Once the new drive is confirmed to be working OK, the source (old) drive can be connected using the USB Dock to be formatted/blanked out in order to use as a backup drive or whatever.
I'd strongly advice to NOT do anything with the old drive. Just keep it as is as a backup only. Get another new/blank drive to use as storage, if needed.
Final note: Albeit being much slower, to clone a drive to use in the same exact machine, hardware based cloning can be more practical for most.
I didn't get into software based cloning because it has been covered on the forums before (please search for it).