Corruption!

[Guest]

Hi,

I have tried to open a 'Frontend' database this morning to be told the
Backend 'Is not an Access database and needs to be repaired'.

I have tried Repairing/Compacting the Backend but get told it is not a valid
database file.

I am using Access 97.

Is there anyway of retrieving the information from the Backend? I have tried
various things but get the same kind of errors.

Does anyone know why this happens and how it can be prevented in future?
(There are approx 10 users for the DB and I have now lost all of yesterdays
work

Cheers,
Steve.

 

[Arvin Meyer]

First, always work on a copy of the database. Working on the original may
make it impossible for a repair service to fix it.

Download a copy of JetComp.exe:

http://support.microsoft.com/default.aspx?scid=kb;EN-US;273956

Also have a look at the Microsoft KB article:

http://support.microsoft.com/default.aspx?scid=kb;EN-US;209137

Then have a look at Tony Toews' Access Corruption FAQ at:

http://www.granite.ab.ca/access/corruptmdbs.htm

for some suggestions. Unfortunately, some corruption cannot be fixed - you
may need to create a new database, import what can be salvaged, and recreate
the rest.

Although it's a paid service, Peter Miller does an outstanding job of saving
corrupt databases. Try this URL:

http://www.pksolutions.com
--
Arvin Meyer, MCP, MVP
Microsoft Access
Free Access downloads:
http://www.datastrat.com
http://www.mvps.org/access

 

[Tom Wickerath]

Hi Steve,

See the following articles for suggestions on what causes corruption:

Allen Browne's site:
Preventing corruption
http://members.iinet.net.au/~allenbrowne/ser-25.html

Recovering from corruption
http://members.iinet.net.au/~allenbrowne/ser-47.html


Tony Toews site. Note: you can search Tony's site for keywords, such as corruption, and find
lots of hits. Here are a few of them:

Corrupt Microsoft Access MDBs FAQ
http://www.granite.ab.ca/access/corruptmdbs.htm

Best Practices for Microsoft Access
http://www.granite.ab.ca/access/bestpractices.htm

ACC: Jet Database Engine 3.x Error Messages Due to Corruption
http://support.microsoft.com/?id=182867


_____________________________________________


Hi,

I have tried to open a 'Frontend' database this morning to be told the
Backend 'Is not an Access database and needs to be repaired'.

I have tried Repairing/Compacting the Backend but get told it is not a valid
database file.

I am using Access 97.

Is there anyway of retrieving the information from the Backend? I have tried
various things but get the same kind of errors.

Does anyone know why this happens and how it can be prevented in future?
(There are approx 10 users for the DB and I have now lost all of yesterdays
work

Cheers,
Steve.

 

[Tom Wickerath]

Arvin,

Is Peter Miller still offering this service? The reason I ask is that Access MVP Alex Dybenko
includes the following post, dated 10/1/2004, at http://alexdyb.blogspot.com/:

"Well, looks promising, hope this will be a good replacement for Peter Miller, who suddenly stop
this service..."

Out of curiosity, I sent the following inquiry to Peter Miller. As of today, I have not received
any reply back.


From: Tom Wickerath
To: (e-mail address removed)
Sent: Saturday, October 02, 2004 11:34 PM
Subject: Alex Dybenko’s blog


Received the following from a friend of mine. Is there any truth to this?

Just wondering...

Tom Wickerath
Bellevue, WA.

_________________

From my friend:

In Alex Dybenko’s blog, he mentions the Access repair and recovery service, Atroplan.com. Alex’s
English is just good enough that I can’t figure out if he was slamming Thilo’s new service, Tony
Toews’s services, or praising one of them. See the blog entry for 1 Oct. ’04:
http://alexdyb.blogspot.com

Alex also mentions that Peter Miller’s PKSolutions isn’t recovering databases any more. I wonder
what’s up with that. The PKSolutions Web site is still up.

___________________________________________


First, always work on a copy of the database. Working on the original may
make it impossible for a repair service to fix it.

Download a copy of JetComp.exe:

http://support.microsoft.com/default.aspx?scid=kb;EN-US;273956

Also have a look at the Microsoft KB article:

http://support.microsoft.com/default.aspx?scid=kb;EN-US;209137

Then have a look at Tony Toews' Access Corruption FAQ at:

http://www.granite.ab.ca/access/corruptmdbs.htm

for some suggestions. Unfortunately, some corruption cannot be fixed - you
may need to create a new database, import what can be salvaged, and recreate
the rest.

Although it's a paid service, Peter Miller does an outstanding job of saving
corrupt databases. Try this URL:

http://www.pksolutions.com
--
Arvin Meyer, MCP, MVP
Microsoft Access
Free Access downloads:
http://www.datastrat.com
http://www.mvps.org/access

 

[Brian]

Hi,

I have tried to open a 'Frontend' database this morning to be told the
Backend 'Is not an Access database and needs to be repaired'.

I have tried Repairing/Compacting the Backend but get told it is not a valid
database file.

I am using Access 97.

Is there anyway of retrieving the information from the Backend? I have tried
various things but get the same kind of errors.

Does anyone know why this happens and how it can be prevented in future?
(There are approx 10 users for the DB and I have now lost all of yesterdays
work

Cheers,
Steve.

Occasional corruptions are a fact of life with multi-user Access databases.
Even if your network is rock-solid and never suffers from glitches, you
could still get the occasional workstation or Access crash which leaves the
database in a corrupt state.

I once got so cheesed off about losing a load of work that I built a little
job which I ran with the Windows scheduler to copy the database file every
30 minutes. Pete Miller told me in a NG that I was running the risk of
getting a corrupt copy by copying a database while people had it open, but
I've been doing it for years now, and, despite having to recover for real a
couple of times, and regularly testing the backup files, I've never
encountered a corruption in the copies.

 

[Arvin Meyer]

I haven't spoken with Peter in quite some time, so I can't be sure if he is
still active. OTOH, his service is the only one that I have any personal
experience with (he once recovered a 2 GB JET/Exchange database for 1 of my
clients) so he is the only one I can personally recommend. I have only lost
a few records, and never so much as a table, much less an entire database.
Except during development of a front-end, I've never lost any forms and
never a report. A repair or JetComp or importing into a new database
container, has always recovered practically everything. I've lost more Word
files than had Access corruption. That's in almost 12 years of development,
so I've never needed Peter to repair an Access database.
--
Arvin Meyer, MCP, MVP
Microsoft Access
Free Access downloads:
http://www.datastrat.com
http://www.mvps.org/access

 

[Douglas J. Steele]

I don't know about Peter, Tom, but I think I can help out interpretting
Alex's blog entry!

IIRC, Thilo contacted Tony (doubtlessly because of the Corruption FAQ Tony
has). Thilo had sent a number of corrupted databases to many of the other
companies claiming to offer recovery services, and those other companies
were unable to recover the databases Thilo sent them. Thilo was able to
recover all of them.

--
Doug Steele, Microsoft Access MVP

(No private e-mails, please)

From my friend:

In Alex Dybenko’s blog, he mentions the Access repair and recovery

service, Atroplan.com. Alex’s

 

[Arvin Meyer]

Occasional corruptions are a fact of life with multi-user Access databases.
Even if your network is rock-solid and never suffers from glitches, you
could still get the occasional workstation or Access crash which leaves the
database in a corrupt state.

While corruption occasionally happens, it is rare, even with a crash.

I once got so cheesed off about losing a load of work that I built a little
job which I ran with the Windows scheduler to copy the database file every
30 minutes. Pete Miller told me in a NG that I was running the risk of
getting a corrupt copy by copying a database while people had it open, but
I've been doing it for years now, and, despite having to recover for real a
couple of times, and regularly testing the backup files, I've never
encountered a corruption in the copies.

Copying any open file, not just an Access file, can cause it to corrupt. It
happens if it is being written to while you are copying. Professional backup
programs generally intercept and buffer incoming data while they are
copying. The chances are that it won't corrupt, or won't corrupt enough to
make it unusable, but it can corrupt, so Peter was correct.
--
Arvin Meyer, MCP, MVP
Microsoft Access
Free Access downloads:
http://www.datastrat.com
http://www.mvps.org/access

 

[Brian]

While corruption occasionally happens, it is rare, even with a crash.

In last six years an unrecoverable corruption has happened to me a few times
with a development database and once with a live one. Even so, on each
occasion it was inconvenient and expensive enough to make it worth taking
reasonable steps to minimise the loss if it happened again.

The chances are that it won't corrupt, or won't corrupt enough to
make it unusable, but it can corrupt, so Peter was correct.
--

I didn't say he was wrong, only that it hadn't happened. However, my
mechanism keeps a rolling two day's worth of half hourly copies (weekdays,
working hours only: disc space, though cheap, is not unlimited!). So, in
the highly unlikely event of BOTH a database corruption occurring, AND the
most recent half-hourly copy being unusable, I'm still only gonna lose an
hour's work: much better than losing a day!

 

[Guest]

Thanks for the replies everyone.

I think it is just one of them things! I have requested a backup from my IS
department, which should restore me back the end of play last night (unless
of course thats when it got corrupted.........)

Is there a way of telling between an Access97 .ldb file and an Access 2000
..ldb file?

Steve.

 

[Tom Wickerath]

Hi Doug,

I read that claim too. It didn't pass the smell test with me.


Tom
________________________________________________


I don't know about Peter, Tom, but I think I can help out interpretting
Alex's blog entry!

IIRC, Thilo contacted Tony (doubtlessly because of the Corruption FAQ Tony
has). Thilo had sent a number of corrupted databases to many of the other
companies claiming to offer recovery services, and those other companies
were unable to recover the databases Thilo sent them. Thilo was able to
recover all of them.

--
Doug Steele, Microsoft Access MVP

(No private e-mails, please)

From my friend:

In Alex Dybenko’s blog, he mentions the Access repair and recovery

service, Atroplan.com. Alex’s

 

[Arvin Meyer]

So, in
the highly unlikely event of BOTH a database corruption occurring, AND the
most recent half-hourly copy being unusable, I'm still only gonna lose an
hour's work: much better than losing a day!

I think that's a good idea. How large is the database you are backing up? Do
you use a scheduler to turn on the backup utility? Or just use an Access
database with a timer form to do it?
--
Arvin Meyer, MCP, MVP
Microsoft Access
Free Access Downloads
http://www.datastrat.com
http://www.mvps.org/access

 

[Arvin Meyer]

No not really. They are both Fixed width (32 character) text files.
--
Arvin Meyer, MCP, MVP
Microsoft Access
Free Access Downloads
http://www.datastrat.com
http://www.mvps.org/access

 

[Brian]

I think that's a good idea. How large is the database you are backing up? Do
you use a scheduler to turn on the backup utility? Or just use an Access
database with a timer form to do it?
--
Arvin Meyer, MCP, MVP
Microsoft Access
Free Access Downloads
http://www.datastrat.com
http://www.mvps.org/access

The live (A2002, recently upgraded from 97) back-end is currently just under
200Mb compacted (which gets done automatically every night, so it never gets
much larger than it's compacted size). I've never actually had to recover
it from one of my half-hourly backups: the only time that it got
unrecoverably corrupted was what prompted me to devise this backup scheme,
but it's been OK since. I do, however, check the occasional backup file.

I also use the technique on my development system for development databases,
which obviously can be a wide range of sizes and are much more likely to get
damaged than a live back-end. I have had to go back to one of my copies on
2 or 3 occasions.

I use the Windows scheduler.