I am working ArcMap software. How can I find out Personal Geodatabase Version? I have client file. But I want to find out which version they have to used. I am looking for your guidance
This is NOT the preferred method, and is not recommended as it may lead to corruption of you geodatabase. Only attempt this after making a backup copy of your data.
If you do not have ArcGIS and need to figure out the release number of a Personal Geodatabase (*.mdb), you can also open it in MS Access. If the GDB is pre-10.0, you can look in the GDB_ReleaseInfo table. To determine the version look in the following columns:
If you have a post-10.0 Personal GDB, this information is buried in XML. To find the similar details, look in the GDB_Items table, PhysicalName='WORKSPACE', and read the XML in the Definition column. For example:
NOTE: I had to change the <> to  to get the XML data to show up in this posting.
I do not know of any similar techniques for the FILE Geodatabase.
I'm not sure if Personal Geodatabases are any different, but in ArcCatalog you can right-click on the name of a File Geodatabase, then have a look in the Upgrade Status section of the General tab of the Database Properties dialog that appears. I am currently using ArcGIS 10, and the Upgrade Status section of a version 9.3 File Geodatabase says the following:
(I am sure there is probably a better solution.)