Well, there are at least 2 ways to do this. One is using built-in Windows tools and the other involves using downloading 3rd party tools to assist with this process.
The most important thing you need to know first is whether or not both your Logical drives (C: and D: drive) exist on the same
PHYSICAL HARD DRIVE OR NOT! I'm going to give you a way to do this using the first method, built-in Windows tools, to accomplish this. It of course will only work if both your logical drives are on the same physical hard drive. If you have C: drive on 1 physical hard drive and your D: drive on a 2nd physical hard drive, this won't work and it becomes more difficult to do, which I won't tell you how to do unless you post back that this is your current scenario.
Next, before proceeding it looks like you might have a lot of data on your D: drive which of course you don't want to lose. Regardless of the method or tools used you should first
BACKUP ALL THE DATA YOU HAVE ON YOUR D: DRIVE TO EXTERNAL MEDIA TO AVOID IRRETRIEVABLE DATA LOSS SHOULD YOU MAKE A MISTAKE DURING RE-PARTITIONING!!
Now that you've done your backup, you can take a look at this short video to explain how to combine your C: drive and D: drive into one single large partition (195.54GB). Here's the video:
convert C: partition in Windows to use full drive capcity - Bing video
**REMEMBER: This will only work if both C: and D: drives are on 1 single hard drive, not 2 drives!!**
Once you've completed the combining of the 2 volumes into 1 large new C: drive, you can then copy back all of the Data that was on the old D: drive onto folders on the new C: drive. You will then have
ALL of your files and programs on one single larger C: drive as you asked!
You may ask if there is a way to do this without having to first backup and erase your large D: partition, and the answer is yes; but it takes Linux tools such as GPartEd partition editor and advanced computer knowledge to do so. Even then, it doesn't always work on all computers; and too if your hard drive is older than 3 years old, and has or is failing, this could also cause things to go wrong. That's why it's always important to backup any Data partition you intent to combine with an existing partition. I'm recommending that you use the method in the video first, as it's most likely to work for the person with average computer skills.
Enjoy!
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