All .dmg D'Ls result in Error-536870208_Failed to Mount!?

Question

HI...first time post(er). Not sure why or when, but ALL D/Ls of S/W Fail to Mount. DiskImageMounter and Disk Utility are unsucceessful. Running 10.3.9 on a 450 Yosemite w/1GB RAM and a 160GB HD w/ four partitions (kinda lenghty, but it might prove helpful to someone (:)...and I know now I "lost" 32GBs in my process, ... .dmg did function, but not for the last week or so.
WDC WD1600JB-00GVA0:
Capacity: 128 GB
Model: WDC WD1600JB-00GVA0
Revision: 08.02D08
Serial Number: WD-WCAL94603469
Removable Media: No
Detachable Drive: No
BSD Name: disk0
Protocol: ATA
Unit Number: 0
Socket Type: Internal
OS9 Drivers: Yes
JAGUAR(10.2):
Capacity: 8 GB
Available: 6.24 GB
Writable: Yes
File System: Journaled HFS+
BSD Name: disk0s9
Mount Point: /Volumes/JAGUAR(10.2)
PANTHER(10.3):
Capacity: 10 GB
Available: 7.08 GB
Writable: Yes
File System: Journaled HFS+
BSD Name: disk0s10
Mount Point: /
TIGER(10.4):
Capacity: 35 GB
Available: 26.99 GB
Writable: Yes
File System: Journaled HFS+
BSD Name: disk0s11
Mount Point: /Volumes/TIGER(10.4)
OS9.2:
Capacity: 8 GB
Available: 7.75 GB
Writable: Yes
File System: Journaled HFS+
BSD Name: disk0s12
Mount Point: /Volumes/OS9.2
FREEDOM:
Capacity: 67 GB
Available: 66.95 GB
Writable: Yes
File System: Journaled HFS+
BSD Name: disk0s13
Mount Point: /Volumes/FREEDOM
Thanx in advance for any/all assistance!
B&WG3, G4Sawtooth, & Legacy Models   Mac OS X (10.3.9)   My "On-Line" Mac is the B&W 450mhz/1GB RAM/160GB HD, (10.3.9).

Answer 1

Welcome first time poster!
I presume you are talking about mounting the .dmg in Panther, as this is the Panther forum and you have a lot of OS's installed. OK.
As that error is quite general, best apply a general remedy, which is the suggestion to run Repair Disk from your OS.
To do this: Insert the Panther CD Install Disk 1 into the drive and then select Restart; when you hear the chime hold down C key until the apple logo appears.
This will take you to the installation software, but you do not want to install.
Select your language, then go up to the top menu bar to Installer and navigate to the Disk Utilities application.
Select the Panther start up drive, then follow the instructions in the First Aid pane where you can click on Repair Disk.
If it finds errors, repeat the process until it reports no errors.
After these repairs, quit the application, and restart normally.
Once restarted normally run Repair Permissions. from the Disk Utility application found on your hard drive in Application/Utilities.
See how that works.
regards roam