Hi,

A client sent me an Access 2007 db.accdb which I modified using 2010.
The client could not open using Access 2007 "Unrecognized database
format 'C:\RD\db.accdb".

I tried to open using Access 2007 and got the same message.

Does anyone have an explanation??

Cheers,
Barry

"Barry Edmund Wright" <barry.edmund.wright (AT) witstoronto (DOT) ca> wrote

Explanation: It's easy to look back and make a version backward compatible
because you can see and test with the older version (Access 2010
successfully opens the Access 2007 database) ; it's not nearly so easy to
look forward and make a version (in your case Access 2007) forward
compatible with whatever may be done in the _next_ version (Access 2007 not
opening the database once it's been modified and saved in Access 2010).

This is a known issue, discussed many times here in the newsgroup. What we
don't know is whether Microsoft _thought_ they'd implemented both backward
and forward compatibility in Access 2010.

--
Larry Linson
Microsoft Office Access MVP
Co-Author, Microsoft Access Small Business Solutions, Wiley 2010

"Barry Edmund Wright" wrote in message
news:8d50cbbe-0804-40ed-a420-3f13d1da89f3 (AT) hs8g2000vbb (DOT) googlegroups.com...

In a nutshell the basic problem is Access 2007 and 2010 use + share the same
format, but have different features.

In the past this has occurred. For example Access 2002 and 2003 don't have a
separate file versions. They share the SAME version.

The policy is quite much that two versions of office in a row now have to
use the same file versions. This "hopefully" allows easy of upgrade and
switching.

For most of office this works rather well. I mean from office 2000 all the
way up to office 2003 (3 versions of office), you only have two file
versions. And even more interesting was the defaults for most office 2003
applications were to use 2000 file formats.

So over a span of quite a few years, and over a span of THREE office
releases there was VERY little issues in terms of switching from one version
of office to the next.

On other hand, when I attempted to support and develop using Access 2003 for
Access 2000 clients, I found that even after delivering the 2000 file, and
THEY on site created the mde, a good number of bugs and issues resulted
(note how THEY were creating the mde with a2000). In fact, the only fix was
to do a de-compile on-site in Access 2000, then re-compile, and THEN create
the mde in 2000. When we did this, EVERYTHING worked fine in the mde.

So nearly 10+ years ago I learned that it is a very bad idea to modify or
develop Access applications and send them backwards.

In fact even going back to the old DOS days of FoxPro etc., we always found
that moving forward to the next version was easy, but sending something
backwards was a risky proposition. So this is not new, and our industry has
a long history in this regards (and so does Access have many past examples
of this issue).

Ok, so building on the lessons learned above from basic history and
experience in my industry, a few things:

Install all the SP2 packs to office 2007. A number of updates "improved"
the warnings and in fact would allow 2007 to open tables with 2010 features,
but they would become READ ONLY. You want to ensure updates are also issued
to ACE (the data engine) since these updates are required for opening of
tables.

If you have to share the database between the two versions, then use a LOWER
common denominator. Just like you could not use 2003 features in 2002, the
file formats because they where the SAME. This made it very difficult to
know or tell when you do something that would cause a failure in 2002. The
difference between the 2002/2003 file format and the 2007/2010 file format
is Access had such a HUGE number of changes in 2010.

So use the 2002/2003 format with 2007/2010. This will prevent you from using
2010 features into that mdb file, and BOTH will open the file without issue.

As I stated, I think due HUGE number of changes in 2010, Access 2010 MOST
certainly should have received a new file version. However there is that
"nasty" policy for office that says no new file formats for "2" office
versions. As noted we seen this done in the past (2002/2003). However,
changes from 2002/2003 where not that great whereas changes from 2007 to
2010 are.

So while I had problems in FoxPro DOS days, and even using Access 2003 to
send files back to 2000 users, then this simply suggests that sending files
back to previous versions can be problematic.

So, from all this:

Use a common lowest format that forces features to be restricted. So use the
2002/2003 format if you have to send data between 2007 2010. You have to do
this since we don't have a 2007 only format.

Have them install office sp2, for 2007. Then access 2007 should be able to
open the file. However tables with CALCULATED columns cannot be opened.
Also, tables with data macros (the new TRIGGER code) CAN be opened, but they
will be read only. You get a message to that effect (again, office sp2 for
2007 must be installed else you get the invalid format message).

An outline of the steps you have to take to allow this file to be used in
previous versions is outlined here:

http://msdn.microsoft.com/en-us/office/cc907897.aspx

At the end of the day, this issue nor problem is not any different then back
in the FoxPro DOS days, the Access 2003 days, or today in the Access 2010
days.

I do think however what is different here is the relative ease in which
touching the file with 2010 can cause issues with 2007.

And I think in this case the release cycle and the "policy" of forcing the
same file format may have helped most of the office programs,
but in the case of Access I think such a "same file" policy has hurt more
than it helped IMHO. In other words, a policy designed to make this
situation better has in fact made it worse.


--
Albert D. Kallal (Access MVP)
Edmonton, Alberta Canada
Pleasenospam_kallal (AT) msn (DOT) com

"Barry Edmund Wright" <barry.edmund.wright (AT) witstoronto (DOT) ca> wrote


As has been pointed out, this is a common problem. Very frustrating - mostly
because Access doesn't point out when you're using a feature that isn't
compatible with Access 2007, and doesn't help you find it when you do. I've
run into this many times.

Oftentimes is the "empty cell" feature that gets you, if you use cells with
your forms.

Best thing is to create an Access 2007 database, and try to export your
forms, one by one, from 2010 to 2007. When you come across the form that's
causing the problems, you won't be able to export it. That should help you
narrow it down to find where the problem(s) is/are.