Question m.2 & SSD issues

[aaro9590]

I just installed a new 960 EVO 1TB m.2. However, after installing, my other 500GB SSD has disappeared and I can no longer access it. Wondering if anyone can help me set it up. I want my 250 GB 950 PRO m.2 to be my main boot drive, with my other 1TB 960 EVO m.2 as a secondary and my other 500GB SSD as another backup.
Thanks for the help in advance.

Edit: I can see the 500GB SSD in my File Explorer, but it has a blue "?" and I can't click on it.

 

[rgd1101]

full system spec

 

[aaro9590]

OS Name Microsoft Windows 10 Home
Version 10.0.17763 Build 17763
Other OS Description Not Available
OS Manufacturer Microsoft Corporation
System Name DESKTOP-QMODOHP
System Manufacturer MSI
System Model MS-7976
System Type x64-based PC
System SKU Default string
Processor Intel(R) Core(TM) i7-6700K CPU @ 4.00GHz, 4008 Mhz, 4 Core(s), 8 Logical Processor(s)
BIOS Version/Date American Megatrends Inc. 1.C0, 5/11/2016
SMBIOS Version 3.0
Embedded Controller Version 255.255
BIOS Mode UEFI
BaseBoard Manufacturer MSI
BaseBoard Product Z170A GAMING M7 (MS-7976)
BaseBoard Version 1.0
Platform Role Desktop
Secure Boot State Off
PCR7 Configuration Binding Not Possible
Windows Directory C:\WINDOWS
System Directory C:\WINDOWS\system32
Boot Device \Device\HarddiskVolume4
Locale United States
Hardware Abstraction Layer Version = "10.0.17763.529"
User Name DESKTOP-QMODOHP\Aaron
Time Zone Eastern Daylight Time
Installed Physical Memory (RAM) 32.0 GB
Total Physical Memory 32.0 GB
Available Physical Memory 26.8 GB
Total Virtual Memory 34.0 GB
Available Virtual Memory 26.6 GB
Page File Space 2.00 GB
Page File C:\pagefile.sys
Kernel DMA Protection Off
Virtualization-based security Not enabled
Device Encryption Support Reasons for failed automatic device encryption: TPM is not usable, PCR7 binding is not supported, Hardware Security Test Interface failed and device is not InstantGo, Un-allowed DMA capable bus/device(s) detected, TPM is not usable
Hyper-V - VM Monitor Mode Extensions Yes
Hyper-V - Second Level Address Translation Extensions Yes
Hyper-V - Virtualization Enabled in Firmware Yes
Hyper-V - Data Execution Protection Yes

 

[rgd1101]

https://www.msi.com/Motherboard/Z170A-GAMING-M7/Specification
* M.2, SATA and SATAe ports maximum support 1x M.2_PCIe + 6x SATAs or 1x M.2_SATA + 1x M.2_PCIe + 4x SATAs.

read the manual to see which is disable

 

[popatim]

The diagram is on page 35 of the manual.