determine MS Access version by binary read of mdb,mde

[dgm]

Sometime ago I wrote a VB6 program to launch the correct version of MS
Access, depending on what version a file was made with. The program grabs all
the MS Access file types when it loads and after a delay does the same again.
Upon clicking an MS Access file type, the program reads the first 176 bytes
from the file then launches either Access 97 or Access 2000 depending on
what's found.

I'm having to maintain several old databases, continuing with the same
version. Users also need help opening the right version of Access for a file.
The program needs to be updated. All I have myself is 97 and 2000, but users
have all subsequent versions. I have no way of creating sample files for each
of the versions so I can see what they contain.

My logic to determine 97 or 2000 in the first 176 bytes is, if the string
"Standard Jet" is not found or if the string "4.0" is found, the file is
2000. Otherwise it is 97. The location of the MS Access exe is then fetched
from the shell\open\command value in the registry for that version.

Can someone please say what info in the fle indicates the version created
with, for all versions? I will make the updated program available for anyone
who wants it. Thanks

 

[Douglas J. Steele]

Go to http://www.openaccess.co.za/BlackAndWhiteInc/AccessOpener.htm, sign
the NDA agreement and Donn will send you the information for free.

 

[James A. Fortune]

Sometime ago I wrote a VB6 program to launch the correct version of MS
Access, depending on what version a file was made with. The program grabs all
the MS Access file types when it loads and after a delay does the same again.
Upon clicking an MS Access file type, the program reads the first 176 bytes
from the file then launches either Access 97 or Access 2000 depending on
what's found.

I'm having to maintain several old databases, continuing with the same
version. Users also need help opening the right version of Access for a file.
The program needs to be updated. All I have myself is 97 and 2000, but users
have all subsequent versions. I have no way of creating sample files for each
of the versions so I can see what they contain.

My logic to determine 97 or 2000 in the first 176 bytes is, if the string
"Standard Jet" is not found or if the string "4.0" is found, the file is
2000. Otherwise it is 97. The location of the MS Access exe is then fetched
from the shell\open\command value in the registry for that version.

Can someone please say what info in the fle indicates the version created
with, for all versions? I will make the updated program available for anyone
who wants it. Thanks

The following should get you started:

'---Begin Module Code---
Public Function AccessVersion(strFileName As String) As String
Dim strL1 As String
Dim lngL As Long
Dim intFileNum As Integer

AccessVersion = ""
intFileNum = FreeFile()
Open strFileName For Binary Access Read Shared As #intFileNum
strL1 = Space(LOF(intFileNum))
Get #intFileNum, 1, strL1
Close #intFileNum
lngL = Asc(Mid(strL1, 115, 1))
Select Case CStr(Hex(lngL))
Case "12":
AccessVersion = "A97 mdb/mde"
Case "7f":
AccessVersion = "A2K mdb"
Case "15":
AccessVersion = "A2K2/3 mdb"
Case "69":
AccessVersion = "A2K7 accdb"
Case "ff":
AccessVersion = "A2K7 adp"
Case Else:
AccessVersion = "Unknown"
End Select
End Function
'----End Module Code----

For a blank mdb or mde A97 database the initial bytes were identical.
Perhaps including more bytes further down can distinguish between mdb
and mde files, if you have the files and can examine the bytes . I
didn't look at the mde or accde files for any later versions. Note that
a version of Access newer than A2007, depending on the header structure
(namely, if it uses the same zero-based byte 114 value as a previous
version), can cause this function to misidentify the Access version.
The function also assumes that the lower bytes of the file do not change
(unknown). Perhaps the mdb file structure info from sourceforge.net can
supply that and further information. I don't have the mdb structure
memorized and I don't remember where the mdb information is on
sourceforge.net. Sorry. However, the accdb header seems to follow the
pattern of previous versions. The hex editor I used to look at the
binaries was from:

http://www.kibria.de/frhed.html

frhed ver. 1.1.0

James A. Fortune
(e-mail address removed)

 

[Tony Toews [MVP]]

I don't remember where the mdb information is on
sourceforge.net.

MDB Tools is a set of open source libraries and utilities to
facilitate exporting data from MS Access databases (mdb files) without
using the Microsoft DLLs. Thus non Windows OSs can read the data. Or,
to put it another way, they are reverse engineering the layout of the
MDB file.

http://sourceforge.net/projects/mdbtools/ Download the file and open
the HACKING file.

Tony
--
Tony Toews, Microsoft Access MVP
Please respond only in the newsgroups so that others can
read the entire thread of messages.
Microsoft Access Links, Hints, Tips & Accounting Systems at
http://www.granite.ab.ca/accsmstr.htm
Tony's Microsoft Access Blog - http://msmvps.com/blogs/access/

 

[aaron.kempf]

SQL Server allows this quite easily-- select @@version

Please ignore Tony Toews posting as his answer to every question
requires an obsolete database (Jet).

Maybe if Tony had ever learned a practical database-- then maybe he
wouldn't have a 'when you only have a hammer' syndrome

 

[vanzandt]

Please refrain from posting irrelevant answers. The OP asked how to read the
Access database file in binary from VB6. Your post avoids answering the
question, and doesn't refer to either of the products being asked about.

Maybe it would be better to ignore your posts. Every version of Access, the
topic of this newsgroup, installs and runs the Jet database engine. It's
silly to ignore that fact.

SQL Server allows this quite easily-- select @@version

Please ignore Tony Toews posting as his answer to every question
requires an obsolete database (Jet).

 

[Tony Toews [MVP]]

SQL Server allows this quite easily-- select @@version

An answer totally irrelevant to the question.

Tony
--
Tony Toews, Microsoft Access MVP
Please respond only in the newsgroups so that others can
read the entire thread of messages.
Microsoft Access Links, Hints, Tips & Accounting Systems at
http://www.granite.ab.ca/accsmstr.htm
Tony's Microsoft Access Blog - http://msmvps.com/blogs/access/

 

[James A. Fortune]

MDB Tools is a set of open source libraries and utilities to
facilitate exporting data from MS Access databases (mdb files) without
using the Microsoft DLLs. Thus non Windows OSs can read the data. Or,
to put it another way, they are reverse engineering the layout of the
MDB file.

http://sourceforge.net/projects/mdbtools/ Download the file and open
the HACKING file.

Tony

Thanks Tony.

James A. Fortune
(e-mail address removed)

George: You've never seen that data recovery software before and you're
using it like you've used it for years. It only took about two minutes
from the time you installed it until my Excel files were rescued.

Me: Programmers can make some great guesses about where things should be
in the user interface if the software is written well.

 

[aaron.kempf]

vz;

Jet fucking sucks a mother fucking dick.

Don't insist that people use it-- just because you're too much of a
moron to learn a real DB.

Jet has been obsolete for a decade

-aaron

 

[Larry Linson]

Please ignore Tony Toews posting as his
answer to every question requires an
obsolete database (Jet).

Jim Fortune has been around these newsgroups plenty long enough to know
whose responses to ignore, Mr. Kempf.

Larry Linson
Microsoft Office Access MVP

 

[dgm]

Sometime ago I wrote a VB6 program to launch the correct version of MS
Access, depending on what version a file was made with. The program grabs all
the MS Access file types when it loads and after a delay does the same again.
Upon clicking an MS Access file type, the program reads the first 176 bytes
from the file then launches either Access 97 or Access 2000 depending on
what's found.

I'm having to maintain several old databases, continuing with the same
version. Users also need help opening the right version of Access for a file.
The program needs to be updated. All I have myself is 97 and 2000, but users
have all subsequent versions. I have no way of creating sample files for each
of the versions so I can see what they contain.

My logic to determine 97 or 2000 in the first 176 bytes is, if the string
"Standard Jet" is not found or if the string "4.0" is found, the file is
2000. Otherwise it is 97. The location of the MS Access exe is then fetched
from the shell\open\command value in the registry for that version.

Can someone please say what info in the fle indicates the version created
with, for all versions? I will make the updated program available for anyone
who wants it. Thanks

Pasted below is a module ffrom my VB6 program, updated for later versions of
access. The program has no form and only one module.

Attribute VB_Name = "ChooseAccessModule"
Option Explicit
DefInt A-Z
Private Declare Sub Sleep Lib "kernel32.dll" (ByVal dwMilliseconds As Long)

Sub Main()
Dim a$, file$, p, q, exe$, version$, dbeng As Object, dbs As Object, versi,
verss$
file = Trim(Command)
If Left(file, 1) = Chr(34) Then file = Mid(file, 2)
If Right(file, 1) = Chr(34) Then file = Left(file, Len(file) - 1)
If Len(file) = 0 Then
Setup
MsgBox "Setup complete"
Exit Sub
End If
On Error Resume Next
Close
Open file For Binary Access Read As 1
If Err <> 0 Then
MsgBox "The file:" & vbCrLf & _
file & vbCrLf & _
"was not found or failed to open"
Exit Sub
End If
a = Space(32)
Get 1, 1, a
Close
If Asc(Mid(a, 1, 1)) = 1 _
Then
version = "7"
Else
If Asc(Mid(a, 21, 1)) = 0 _
Then
version = "8"
Else
Set dbeng = CreateObject("DAO.DBEngine.36")
If Err <> 0 Then
MsgBox "The file:" & vbCrLf & _
file & vbCrLf & _
"cannot be opened because the correct version of"
& vbCrLf & _
"Microsoft Access is not installed"
Exit Sub
End If
Set dbs = dbeng.OpenDatabase(file, False, False)
If Err <> 0 Then
Err.Clear
Set dbs = dbeng.OpenDatabase(file, True, False)
If Err <> 0 Then
Err.Clear
Set dbs = dbeng.OpenDatabase(file, False, True)
If Err <> 0 Then
Err.Clear
Set dbs = dbeng.OpenDatabase(file, True, True)
End If
End If
End If
If Err <> 0 Then
Set dbeng = Nothing
MsgBox "The file:" & vbCrLf & _
file & vbCrLf & _
"could not be opened as a Microsoft Access
database"
Exit Sub
End If
versi = Int(Val(dbs.Properties("Version")))
If Err <> 0 Then versi = 0
Err.Clear
verss = dbs.Properties("AccessVersion")
If Err <> 0 Then verss = ""
dbs.Close
Set dbs = Nothing
Set dbeng = Nothing
Select Case versi
Case 3
version = "8" '97 format
Case 4
Select Case verss
Case "08.50" '2000 format.
version = "9"
Case "09.50" '2002/3 fomat.
version = "11" 'try 2003 first
End Select
Case 12
version = "12" '97 format
End Select
End If
End If
If Len(version) = 0 Then
MsgBox "The file:" & vbCrLf & _
file & vbCrLf & _
"could not be interrogated for Microsoft Access version"
Exit Sub
End If
exe = RegFunGetValue(HKEY_CLASSES_ROOT, "Access.Application." & version &
"\shell\open\command", "", "")
If Len(exe) = 0 And version = "11" Then
version = "10"
exe = RegFunGetValue(HKEY_CLASSES_ROOT, "Access.Application." & version
& "\shell\open\command", "", "")
End If
If Len(exe) = 0 Then
MsgBox "The correct version of Microsoft Access" & vbCrLf & _
"is not installed for file:" & vbCrLf & _
file
Exit Sub
End If
If InStr(exe, "%1") = 0 Then
MsgBox "Invalid Microsoft Access open command at:" & vbCrLf & _
"Access.Application." & version & "\shell\open\command"
Exit Sub
End If
exe = Replace(exe, "%1", file)
Err.Clear
Shell exe, vbNormalFocus
If Err <> 0 Then
MsgBox "The following command failed to execute:" & vbCrLf & _
exe & vbCrLf & vbCrLf & _
Err.Description
Exit Sub
End If
Sleep 7000
Setup
End Sub

Private Sub Setup()
Dim a$, exe$, f1
exe = App.Path
If Right(exe, 1) <> "\" Then exe = exe & "\"
exe = exe & App.EXEName & ".EXE"
For f1 = 7 To 12
a = "Access.Application." & f1
If Len(RegFunGetValue(HKEY_CLASSES_ROOT, a & "\shell\open\command", "",
"")) > 0 Then
RegFunSetValue HKEY_CLASSES_ROOT, a & "\shell\ChooseAccess\command",
"", """" & exe & """ ""%1""", REG_VB_STRING
RegFunSetValue HKEY_CLASSES_ROOT, a & "\shell", "", "ChooseAccess",
REG_VB_STRING
End If
Next f1
End Sub

' UPDATED: 05-30-2003 [ID]:dgm4B0FkJgNcdY
' UPDATED: 08-13-2005 [ID]:dgm9cr6NO5gbAJ