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Inbox.mbx, Inbox.dbx  versus Inbox.idx

Jeanne061397 asked
I've been helping a friend who owns an old 4 year old computer try to free up space as he is running out rapidly.  We look in the find files, advanced, looked for files that are at least 2000 kb to help find the real disk space hogs.

We found huge files listed as inbox.mbx, outbox.mbx, sent files.mbx (these may be related to Internet Mail & News).  We also found large files with the following extensions:
inbox.dbs, deleted.dbx located in Windows/Application Data/Identity - etc.

We also saw in this window files named delte.idx and inbox.idx.

He is using Outlook Express and Internet Explorer 5.

Could you tell me if any of these files are old and can safely be deleted from his computer.  We just don't want to delete the wrong inbox files.

Thank you for your help.

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You don't want to delete them; however, you can delete the stuff that is IN them (the old messages). Then go to Tools/Options/Maintenance and change the settings to clean up your email system.

Personally, I'd start by doing a File/Find on *.bak and *.tmp files, and then going into his IE and clearing out all the Internet files (the cache). Then run something like Norton Utilities on it to defragment the drive. You'll probably pick up a ton of space.


Actually you can delete the files with the extensions of .idx or .mbx.  These files were used by Outlook Express prior to version 5.0, and there was one of each per folder in OE.  

OE 5 and higher use the .dbx files (the index is built in so there is only one file per folder in OE).  For these delete unneeded emails within OE and then compact as ericpete mentioned.

As OE5 doesn't/can't use .idx and .mbx files the only way to reclaim the space they are taking up is to delete the actual files from the harddrive.  

If you just look at the modified date on these files you'll see that they haven't been used since OE was updated to 5+, and the email was imported from them into the new .dbx files.


Travel, that's what I thought that they could be safely deleted as the dates on them were old ones.

Thanks for your help.  I'll tell my friend to delete them.