Hey Leo,
Let’s try giving full control to the drive and check.
a. Right-click the drive and select Properties.
b. Click on the Security tab.
c. Click Advanced in the lower right.
d. In the Advanced Security Settings window that pops up, click on the Owner tab.
e. Click Edit.
f. Click other users or groups.
g. Click Advanced in the lower left corner.
h. Click Find Now.
i. Scroll through the results and double-click on your current user account.
j. Click OK to all of the remaining windows except the first Properties window.
k. Select your user account from the list up top and click Edit.
l. Select your user account from the list up top again and then in the pane below, check Full control under Allow, or as much control as you need.
m. You’ll get a security warning, click Yes.
Take a look at the below link which talks about the similar issue:
Troubleshoot "access denied" when opening files or folders
Note: Though the links says it is for Windows Vista, it holds good for Windows 7 as well.
Regards,
Savan – Microsoft Support.