How To Fix "Unable To Connect To Access Database" Error


Trying to connect your Access Database and each time you are doing this your database throws error “unable to connect Access database”?  Do you have any idea why you are getting this specific error warning? Well if you are dealing with this issue then just give it try to the following fixes mentioned in this blog.

Take a look over the scenario that one of the users like you is facing with. after then we will discuss about different “Unable To Connect Access Database” errors and their fixes.

Practical Scenario:

I’ve had a working connection to a local Access 2010 db working for over a year on a Windows 7 64-bit machine. The Driver selected is the Microsoft Access Driver (*.mdb, *.accdb). A few days ago I upgraded to Office 2013, and the connection fails with the error “Data Source Name not found, and no default driver selected.” 

In the driver list the Microsoft Access Driver now has (*.mdb) only in the parentheses, instead of both *.mdb and *.accdb. If I look in the ODBC Data Sources dialog, however, the driver is listed as Microsoft Access Driver (*.mdb, *.accdb) — it has both listed. What’s going on? 

Circumstances Under Which Access Database “Unable To Connect Database” Error Encounters

Well there are several types of “Unable To Connect Database” error occur in different circumstances.  Have a look over different “Failed to connect to access database” errors one by one:

ERROR 1#[Microsoft][ODBC Microsoft Access Driver] ‘(unknown)’ is not a valid path

Error Description:

Error Name: “[Microsoft][ODBC Microsoft Access Driver] ‘(unknown)’ is not a valid path. Make sure that the path name is spelled correctly and that you are connected to the server on which the file resides”.


Use fully compatible name in database name when creating the DSN in ODBC Administrator as shown in attached snapshot (DSNDatabaseName.PNG)


Example : \\SPOTSUPTSS55\msaccess\ADS_MS_Access.accdb

Also Read:

How To Fix The Access Runtime Error 3847: “ODBCDirect Is No Longer Supported” In Windows 7/8/10 PC?

ERROR 2# Problem creating a connection to a database * .accdb

Symptoms :

Trying to create connection to your Access database .accdb file, while making selection for the .accdb database it shows following of the error warning:

Error: The connection to the data source cannot be established using the defined settings. The server returned the following error:

ODBCError HY024: [Microsoft] [Microsoft Access ODBC Driver] ‘(unknown)’ is not a valid path. Make sure the path is spelled correctly and that it is connected to the server where the file is located.

  • Accessing via web returns following warning:

ADODB.Connection error ‘800a0e7a’
The specified provider could not be found. It may not be installed correctly.
/index.asp, line 43

  • For 64 bit PC drivers are installed.
  • Check that the path in the index.asp, line 43 is correct.

dbcomposition.Open (“Provider= Microsoft.ACE.OLEDB.12.0;Data Source=” & Server.MapPath(“foldername/filename.accdb”))

  • Making a system ODBC 64-bit connection to database from windows ODBC connections manager. Also try to load the page from the browser results in the following message.

2016-12-21 13:35:58 W3SVC16 WIN-83QBT29ETNJ GET /index.asp |44|80004005|[Microsoft][ODBC Driver Manager] The specified DSN contains an architecture mismatch between the Driver and Application. 80 –


How To Fix MS Access Run-time 3146 ODBC Call Failed Error?


The main reason behind this “Cannot Connect To .Accdb database” error is mismatch between the architecture of Windows server, connection drivers and database.


  • Firstly you need to download and install 32 bit version Microsoft Access database engine on windows server available by link.

  • Also check that the driver connection in .asp file is:

{Microsoft Access Driver (*.mdb, *.accdb)}

ERROR 3# Unable To Access A Microsoft Access Database After Adding An OLE DB Connection

Unable To Access A Microsoft Access Database After Adding An OLE DB Connection


When trying to use access database (ACCDB) after adding an OLE DB connection. Then the Microsoft Access table is not added to database connection.


There are several possible reasons for this issue:

  • May be the connection is being tried through ArcMap instead of ArcCatalog.
  • Chances are also that the MS Access database extension (.accdb) is not assigned with the name of the database, while selecting the data source.
  • May be the machine is not having the appropriate driver which is required for Microsoft Access database or is using some different version.
  • If you are using 32 bit database then same 32-bit driver is needed for successful connection. Actually the Driver installation comes along with the installation of Microsoft Access Database Engine.


To fix this “Unable to access a Microsoft Access database after adding an OLE DB connection” issue. Just try out the following fixes.

  • Make connection by ArcCatalog instead of ArcMap. To catch information on  how to connect database in ArcGIS, check out the following article, HowTo: Connect to Microsoft Access 2007 / 2010 (ACCDB) files in ArcGIS.
  • Make sure that your database name must include extension mainly at the time of selecting data source. If database name is specified already with extension. Then rename the database connection by making right click on database name and choosing the Rename option.

ERROR 4# “HY024 ‘(UNKNOWN)’ is not a valid path” when attempting to create nickname for remote Microsoft Access database


Mainly this error arises when the System DNS entry is not defined properly. If your remote database is on network drive or mapped drive, at that time when you select the network drive or mapped driver it will show like X:\server\path\dbname.mdb.  And Federation Server ODBC wrapper won’t accept database name on remote location with driver letter (X:\).

Have A  look:

Resolve Access 1919 – configuring ODBC data source Error


  • Ensure whether you are using correct driver and version is 3.0 or higher for Microsoft Access.2) Specify database path in the following mentioned format:


Just type this above path in the full path when you define a new system in DSN entry.

The new system DSN define must be similar as shown in next screenshot.

a) StartODBC Data Source Administrator.
b) Once you click on System DSN tab select ‘Add…’.

c) This will open the “Create New Data Source” You need to scroll down in this window and select ‘Microsoft Access Driver (*.mdb)’ option then tap to the ‘Finish’ option.

d) After then you will see ODBC Microsoft Access Setup window will get open on your screen. Tap to the ‘Select…’ under ‘Database’ section.

e) After then select database windows gets open up on your computer screen. Here you need to type the database path and name. so just type  “\\server\path\dbname.mdb” path right under the Database Name section and then tap to the ‘OK’ option.

f) Now you are back to ODBC Microsoft Access Setup window. So, assign name to your Data Source then tap to the OK option. This will complete the SYSTEM DSN defining process.

Don’t miss it:

Fix [Microsoft][ODBC Microsoft Access Driver] Cannot Update. Database Or Object Is Read-Only Error

Try The Recommended Option:

If meanwhile the execution of the above manual methods; somehow your Access database data gets deleted or somehow it gets corrupted. Then also you need not to get worried as you have the simple and easiest option to restore your lost access database data. This tricky task is only possible with Access Repair N Recovery Tool.

As this efficient tool is just perfect to resolve any type of corruption issue occurred in your Access Database. It can easily restore the corrupt tables, indexes, queries and relations. You can also recover the password protected forms or modules. So, give it a try when you get stuck into such situation of MS access data loss.

Sum up:

Hopefully the above tutorial has shown you the best ways to fix up your “unable to connect database” issue in your respective Access Database. But if still you have any issue regarding this specific issue or any other access database issues then ask it in our FAQ  section.

How To Fix “Unable To Connect To Access Database” Error?