Thanks for your help.  I tried again and it got me back to the initial problem I had.
 The frontend will start, and the analyzer starts (complains about there not being a
last.root, but other than that it's fine), and then when starting mlogger, I get:

[odb.c:860:db_validate_db] Warning: database corruption, first_free_key 0x0001A4
04
[odb.c:3666:db_get_key] invalid key handle
[midas.c:1970:cm_check_client] cannot delete client info
[odb.c:3666:db_get_key] invalid key handle
[midas.c:1970:cm_check_client] cannot delete client info
[odb.c:3666:db_get_key] invalid key handle


And it continues to shoot out error messages about invalid key handles until I kill
it.  Then trying to start the frontend again fails until I remove the .ODB.SHM file. 
Any other ideas?

> > Hello,
> > 
> > Just did a fresh install of MIDAS from the SVN repository under CentOS and
> > everything compiles fine, but when I go to run the frontend (using dio), I get
> > the following error message:
> > 
> > Connect to experiment ...[odb.c:868:db_open_database] Different database format:
> >  Shared memory is 14, program is 2
> > [midas.c:1763:cm_connect_experiment1] cannot open database
> > 
> > 
> > Any ideas on what the problem could be, or how to fix it?  
> 
> You have an old .ODB.SHM from a previous version in your directoy (note the '.' in
> front, so you need a 'ls -alg' to see it). Delete that file and try again.