kindly review the following link:
device manager is not supported on stack switches, try to use CNA instead:
Old post but hey, I have the answer as I just tackled it. Device Manager was deprecated out of the IOS releases for the 3750s back in 2010. I assume because the size of the updates eclipsed what 16MB of ram could handle.
The reason why the express manager page will not go away is because after the flash the default password is cisco. Change the Switch Password field (this is misleading as this field handles the Level 15 User Account) After you change it, open the switch in a new IE session and you will get prompted for the new password.
Also, if you haven't discovered the Cisco Network Assitant I highly reccomemed it. Better than device manager ever could be.
The reason the Express Setup will not go away and the Device Manager will not come back is the Device Manager is simply not in the new code. If you look in the html/ directory, all that's there are the files for the Express Setup.
I was able to get the Device Manage back by doing a little bit of mix and match between the codes. I installed the latest c3750-ipserviceslmk9-tar.122-55.SE12.tar code bundle that was available which left me with only the Express Setup. I then did the following to move the html directory out of the way and get rid of the Express Setup.
rename flash:/c3750-ipservicesk9-mz.122-55.SE12/html flash:/c3750-ipservicesk9-mz.122-55.SE12/html.bak
I then went back to Cisco's firmware download page and browsed through the older revisions. Back at version 12.2.55-SE1(ED) there is a file for IP SERVICES WITH WEB BASED DEV MGR called c3750-ipservicesk9-tar.122-55.SE1.tar. Perfect. I downloaded that to my system, extracted it, and took a look in the html directory. There are all the files to run the Device Manager. I archived that html directory into html.tar and put it on my tftp server.
Back on the switch, I did
copy tftp://<tftpd-address>/html.tar flash:/c3750-ipservicesk9-mz.122-55.SE12/
And then I extracted it:
archive tar /xtract flash:/c3750-ipservicesk9-mz.122-55.SE12/html.tar flash:/c3750-ipservicesk9-mz.122-55.SE12/
Once it was done extracting I now had a html/ directory with the complete Device Manager.
I browsed to the switch IP address and the Device Manager was all there.
Finally I clean up a bit:
Now, I'll caveat this by saying it's possible there have been fixes in the newer revisions that won't work properly with this older version of the Device Manager but so far from clicking around it seems to work for me.