Search function totally misses some file names

I often search a folder with several layers of subfolders (and then sort by update date) to keep track of versions of things. Just searching a folder and 2-4 layers of subfolders. Just searching by file name, or part of a file name. And Windows 7 routinely MISSES files! This is something that has just worked back to Windows 2, and now all the sudden it doesn't?

Case in point:

Directory structure is MyDocuments-DataMartDocuments-CurrentVersionDocs, with another branch on 3rd tier being MyDocuments-DataMartDocuments-LastVersionDocs. So a 3 level directory hierarchy with two branches. Pretty simple.

I'm looking for all files with a .dm1 extension. So at the explorer window for MyDocuments, I enter in the box on the upper right: dm1.

It finds several Dm1 files in all the different directories, but NOT ODS.Dm1, the file I was looking for, that is in LastVersionDocs.

So I got more specific, and searched for the whole file name: ODS.Dm1. Still can't find it.

I also tried it with .dm1 instead of just dm1 (dm1 is always the extension). No difference.

BUT, if I just navigate there directly to the LastVersionDocs folder, ODS.dm1 is there.

I'm not looking at contents of files, no special indexing requirements, just a simple search. But it did NOT find it.

How is that possible? And is it fixable?

Hey

It sounds to me there is a problem with the windows indexing of files

Can you please check that the folder is included in the indexing options
(Start, Control Panel, Indexing Options)
It will probably show as the Users folder (As your files are in your user folder).. there may be listed exclude directories (I'm thinking AppData off the top of my head, that is normal)

If it is listed, if you click Advanced, there should be a rebuild button, try that..

Here is a link to the Microsoft Help page Indexing

You can also add the specific filetype if really needed (it shouldnt)
Also, is the file format encrypted, if so, it is not indexed by default.

Hope this is a good start