Olmpus DS-2 won't record

To play back messages remotely, first you'll need to have set up your two-digit security code (PIN). You can download a copy of the manual here which gives all the details. Once you've done that, here's how to use the system:

1) Call your telephone number and wait for the system to answer. If the answering system is off, it will answer after about 10 rings and sounds a series of beeps.
2) During the greeting message (or a series of beeps when the answering system is off), press 0 and enter your PIN code within 2 seconds. The answering system announces the current time and the number of messages stored in memory. You hear "To play incoming messages, press zero-two. For help, press one-zero." You will hear a beep.
3) Enter a command within 15 seconds. Each command thereafter must be entered within 2 seconds. These are the available commands:

• 0 then 1 Repeat a Message*
• 0 then 2 Playing incoming Messages
• 0 then 3 Skipping a Message
• 0 then 4 Deleting a Message
• 0 then 5 Stop Operation
• 0 then 6 Answering System On
• 0 then 7 Memo Record/Stop**
• 0 then 8 Greeting Message Record/Stop**
• 0 then 9 Answer System Off
• 1 then 0 Help

* For the Repeat a Message function, press 0 then 1 within about four seconds to repeat the previous message, or press 0 then 1 after about four seconds to repeat the current message.

**For the Memo Record and Greeting Message Record function, the first time you enter the corresponding command, it starts the Recording function. If you want to stop the recording, press 0 then 7, 8 or 5.

4) After the command has finished, you hear intermittent beeps indicating that the system is in the command waiting mode. You may enter another command at this time from the chart above.
5) Hang up when you're done.

Remote Message Retrieval
You can operate your answering system from a remote location using any touch-tone
telephone or the handset.
Remote access away from home
You can check, play, or delete messages, even record a new greeting message when
you are away from home. Additionally, you can turn On or Off your answering system
from a remote location.
Remote access:
1) Call your telephone number and wait for the system to answer. If the answering
system is off, it will answer after about 10 rings and sounds a series of beeps.
2) During the greeting message (or a series of beeps when the answering system is off),
press 0 and enter your PIN code within 2 seconds (see "Setting a PIN Code" in your owners manual.
3) The answering system announces the current time and the number of messages stored
in memory. You hear "To play incoming messages, press zero-two. For help, press onezero".
You will hear a beep.

4) Enter a command within 15 seconds, each command there after must be entered
within 2 seconds. You may select a command from the following chart:
For your convenience
a remote operation
card is provided for
you to use while
away from home, it can be found in the back of your owners manual.
Command Function
0 then 6 Answering System On
0 then 7 Memo Record/Stop **
0 then 8 Greeting Message Record/Stop **
0 then 9 Answer System Off
1 then 0 Help Guidance
Command Function
0 then 1 Repeat a Message*
0 then 2 Playing incoming Messages
0 then 3 Skipping a Message
0 then 4 Deleting a Message
0 then 5 Stop Operation
* For Repeat a Message function, press 0 then 1 within about four seconds to
repeat the previous message, or press 0 then 1 after about four seconds to repeat
the current message.
** For Memo Record and Greeting Message Record function, the first time you enter
the corresponding command, it starts the Recording function. If you want to stop
the recording, press 0 then 7 or 8.

5) After the command has finished, you hear intermittent beeps indicating that the
system is in the command waiting mode. You may enter another command at this
time from the chart above.

6) When you are finished, hang up to exit the system. The answering system
automatically returns to standby.
Your machine automatically has a PIN set of 80.
If you are trying to use remote access from a cellular phone and having trouble: Try changing your tone length on your cell phone to long.

Remote Operation
You can check, play, or delete messages, even record a new greeting message from a
remote location (when you are away from home, or from another room using a
handset). Additionally, you can turn on or off your answering system remotely.
Remote access away from home
You can operate your answering system from a remote location using any touchtone
telephone.
1) Call your telephone number and wait for the system to answer. If the answering
system is off, it will answer after about 10 rings and sounds a series of beeps.
2) During the greeting message (or a series of beeps when the answering system is
off), press 0 and enter your PIN code within 2 seconds (see "Setting a PIN Code"
on page 25).
3) The answering system announces the current time and the number of messages
stored in memory. You hear "To play incoming messages, press zero-two. For
help, press one-zero." You will hear a beep.
4) Enter a command within 15 seconds, each command there after must be entered
within 2 seconds. You may select a command from the following chart:
* For the Repeat a Message function, press 0 then 1 within about four seconds to
repeat the previous message, or press 0 then 1 after about four seconds to repeat
the current message.
**For the Memo Record and Greeting Message Record functions, the first time you
enter the corresponding command, the phone starts recording. If you want to
stop the recording, press 0 then 7, 8 or 5.
5) After the command has finished, you hear intermittent beeps indicating that the
system is in the command waiting mode. You may enter another command at this
time from the chart above.


Command Function Command Function
0 then 1 Repeat a Message* 0 then 6 Answering System On
0 then 2 Playing incoming Messages 0 then 7 Memo Record/Stop**
0 then 3 Skipping a Message 0 then 8 Greeting Message Record/Stop**
0 then 4 Deleting a Message 0 then 9 Answer System Off
0 then 5 Stop Operation 1 then 0 Help

The VT-90 uses 4 CR 2025 batteries. Once you install them you must initialize the unit by holding the "erase all" button for 10 seconds. After a series of blinking the unit is ready again. Good luck.

While you are away from your home or
office, you can use a touch-tone phone,
or a pulse (rotary) phone with a pocket
tone dialer (available through your local
RadioShack store) to enter your PIN and
do any of the following:
• set the phone to answer or not
answer calls
• listen to your messages
• record a new outgoing message
• erase messages
• monitor the room where the phone
is located
Notes:
• You cannot remotely operate the
phone using its handset or another
telephone on the same line as the
phone.
• You can also listen to the message
recorded on Line 2 by making a call
to Line 1’s number (or vice versa).
USING THE TOLL-SAVER
If RING TIME is set to TS (toll-saver),
(see “Setting the Number of Rings” on
Page 15), the phone answers after three
rings if you have new messages (ones
you have not listened to). If there are no
new messages, the phone answers after
five rings. This gives you time to hang
up before the phone answers so you
can avoid unnecessary long-distance
charges.
Note: Toll-saver works only on the line
you called. If Line 1 has no new messages,
but Line 2 has one, the telephone
answers after five rings when you
call Line 1.
USING REMOTE
COMMANDS
Follow these steps to operate the phone
from a remote location.
Note: If you wait more than 15 seconds
between keypresses, the phone sounds
a long beep and hangs up.
1. Dial your phone number and wait for
the phone to answer.
2. If the phone is not set to answer
calls, it answers after about 10 rings
and sounds a series of beeps.
3. When the outgoing message begins
(or the phone sounds a series of
beeps), press #, then enter your PIN
within 2 seconds.
If the PIN is correct, the phone announces
the day and time, then it announces
the number of new and old messages.
The phone plays all new messages,
then beeps about every two seconds to
let you know it is ready to accept remote
commands.
Notes:
• If the phone does not respond, try
entering your PIN again. If you enter
an incorrect PIN three times, the
phone beeps and hangs up.
Remote Operation 27
• When the phone is operating from a remote location, it stops all answering functions
and rC appears on the display on the base. The phone resumes answering
functions when it is no longer in remote operation, if you have not turned it off.
• The remote playback of incoming messages is limited to 4 minutes. If you have
more messages after 4 minutes have passed, you must press # 2 again to listen
to the rest of the messages.
• When using remote operation, you can only delete the current message during
playback. You cannot delete all the messages stored at one time.
The following table shows the remote commands you can use.
Note: Remote operation stops when someone picks up the handset and presses either
LINE 1 or LINE 2 (whichever is flashing), or any phone on the same phone line.
Remote Commands
Press #
then (within
2 seconds:
Function
1 Repeat current message during playback.
2 Play messages.
3 Skip current message during playback.
4 Delete current message during playback.
5 Stop playback, recording, and room monitoring.
6 Set the phone to answer or not answer calls.
7 Record or stop recording a new outgoing message.
8 Play the outgoing message.
9 Switch to the other line (Line 1 or Line 2).
0 Monitor the room where the phone is located for 15 seconds

I have had the chips become corrupt. It honestly has not happened much but It has happened. I have about 100 of these devices being used all day long, and I get about one per year. Try calling (800) 622-6372 for Olympus America. They have never helped me in this situation ( I feel I know more about the device than they do ) but it is worth a try.

I've had the same issue. The surefire solution is to go into the Sub Menu and FORMAT. It wipes the entire internal memory clean -- so be sure you've offloaded everything you need. You'll also need to reset the recording quality, if you have a custom setting, because it defaults to the highest quality. But you'll have all your space back.
I believe when files are deleted via computer, the DS-2 doesn't update itself to recognize the space is freed up. That's why data is gone but memory is not freed.  Good luck.

This may be a little late, you are probably home already, but here it is anyhow:

Remote Operation
You can check, play, or delete messages, even record a new greeting message from a remote
location (when you are away from home, or from another room using a handset).
Additionally, you can turn On or Off your answering system remotely.
Remote access away from home
You can operate your answering system from a remote location using any
touch-tone telephone.
1) Call your telephone number and wait for the system to answer. If the answering system is
off, it will answer after about 10 rings and sounds a series of beeps.
2) During the greeting message (or a series of beeps when the answering system is off),
press 0 and enter your PIN code within 2 seconds (see "Setting a PIN Code" on page 25
or 54).
3) The answering system announces the current time and the number of messages stored in
memory. You hear "To play incoming messages, press zero-two. For help, press one-zero".
You will hear a beep.
4) Enter a command within 15 seconds, each command there after must be entered within 2
seconds. You may select a command from the following chart:
Command Function Command Function

0 then 1 Repeat a Message* 0 then 6 Answering System On
0 then 2 Playing incoming Messages 0 then 7 Memo Record/Stop**
0 then 3 Skipping a Message 0 then 8 Greeting Message Record/Stop**
0 then 4 Deleting a Message 0 then 9 Answer System Off
0 then 5 Stop Operation 1 then 0 Help Guidance
* For Repeat a Message function, press 0 then 1 within about four seconds to repeat
the previous message, or press 0 then 1 after about four seconds to repeat the
current message.
** For Memo Record and Greeting Message Record function, the first time you enter the
corresponding command, it starts the Recording function. If you want to stop the
recording, press 0 then 7 or 8.

5) After the command has finished, you hear intermittent beeps indicating that the system
is in the command waiting mode. You may enter another command at this time from the
chart above.
6) When you are finished, hang up to exit the system. The answering system automatically
returns to standby.

Here is a link to the pdf format owners manual from Uniden for this phone:

http://www.uniden.com/pdf/TRU8885om.pdf

Remote Operation
You can check, play, or delete messages, even record a new greeting message from a
remote location (when you are away from home, or from another room using a
handset). Additionally, you can turn on or off your answering system remotely.
Remote access away from home
You can operate your answering system from a remote location using any touchtone
telephone.
1) Call your telephone number and wait for the system to answer. If the answering
system is off, it will answer after about 10 rings and sounds a series of beeps.
2) During the greeting message (or a series of beeps when the answering system is
off), press 0 and enter your PIN code within 2 seconds (see "Setting a PIN Code"
on page 25).
3) The answering system announces the current time and the number of messages
stored in memory. You hear "To play incoming messages, press zero-two. For
help, press one-zero." You will hear a beep.
4) Enter a command within 15 seconds, each command there after must be entered
within 2 seconds. You may select a command from the following chart:
* For the Repeat a Message function, press 0 then 1 within about four seconds to
repeat the previous message, or press 0 then 1 after about four seconds to repeat
the current message.
**For the Memo Record and Greeting Message Record functions, the first time you
enter the corresponding command, the phone starts recording. If you want to
stop the recording, press 0 then 7, 8 or 5.
5) After the command has finished, you hear intermittent beeps indicating that the
system is in the command waiting mode. You may enter another command at this
time from the chart above.
6) When you are finished, hang up to exit the system. The answering system
automatically returns to standby.

Command Function Command Function
0 then 1 Repeat a Message* 0 then 6 Answering System On
0 then 2 Playing incoming Messages 0 then 7 Memo Record/Stop**
0 then 3 Skipping a Message 0 then 8 Greeting Message Record/Stop**
0 then 4 Deleting a Message 0 then 9 Answer System Off
0 then 5 Stop Operation 1 then 0 Help

Here is a link to a similar model: http://www.swbfreedomphone.com/ib/ibansw/fa970.pdf Here is what it says: TONE REMOTE OPERATION Remote Security Code To access answering functions from an outside line, you will need to enter the three digit security code located on the bottom of your unit. Write this number on the Remote Access Card, which you can keep in your wallet. Remote Turn On If you forget to turn on your unit: 1. Call your unit from a touch-tone phone. 2. Wait 12-14 rings until the machine answers. 3. The FA970 will automatically answer by playing your greeting. You may hang up the phone, and subsequent calls will be answered. Remote Message Playback 1. Call your unit from a touch-tone telephone. 2. After your FA970 answers, it plays the outgoing greeting and beeps once. Dial your three digit security code within 20 seconds after the beep, pressing and holding each digit for 1-2 seconds. Allow a 2 seconds interval between each digit. 3. Your FA970 will sound one beep to indicate the code was entered correctly. (If there are no beeps, enter your code again.) 4. You can press the following buttons on your keypad: Option Press Playback Mailbox 1 Messages (1) Playback Mailbox 2 Messages (2) Record Memo Message (3) Record New Greeting (8) Turn Off Answer Mode (9) If you press ?1? or ?2? (to playback messages), you have the follow options: Option Press Erase Current Message (0) Repeat Current Message (4) Repeat Previous Message (4) repeatedly Stop Message Playback (5) Skip to Next Message (6) To SAVE messages, hang up the telephone. Note: Your FA970 will sound a series of beeps if there are no messages. Remote Record New Greeting If you press 8 (to record new greeting): 1. When you hear a beep, begin recording your new greeting (up to 30 seconds). 2. When you have finished recording your new greeting, press (5). The unit will beep, and the new greeting will playback to you. 3. Hang up the telephone. Remote Record Memo If you press 3 (to record memo message): 1. Within three seconds of pressing ?3?, press ?1? or ?2? to select Mailbox 1 or Mailbox 2. Otherwise, the memo will be recorded in Mailbox 1. 2. When you hear a beep, begin recording your memo (up to 60 seconds). 3. When you have finished recording your memo message, press (5). 4. The corresponding Mailbox message count will be increased by one. To Retrieve Messages when Recording Memory is Full 1. When the message capacity is full, the unit will sound 3 beeps after answering the phone. 2. Within 20 seconds after the 3 beeps, dial your 3 digit security code. 3. Your FA970 will sound one beep to indicate the code was entered correctly.