After Vytautas stated that he updated his GDS-2072E to 300MHz, I start thinking about why was my IDS-2074E stuck to 200MHz.
I start playing with the most recent licences, because I updated my scope some time ago, before the latest code released by tv84. Messing around with them, the scope kept stating that the licenses were already installed, until... i tried the 100MHz. Result: my scope downgraded form 200 to 100. Nice!
Trying to reinstall 200 or 300 licences didn't work. Scope "said" that they were already installed, but didn't get me there. It was stuck in 100MHz.
OK! Time to play with the scope once again, to fix my mistake.
Solution:
I think it is sufficient to restore the /home/dso/OptionConf file if you want to remove the installed licenses.
1) Downgraded the firmware to 1.21b6 and establishing an SSL connection to the scope deleted the file OptionConf.
EDIT: Be very careful not to delete all files or the folder2) After that, just a quick check to system info, and the bandwidth info was gone (as expected).
3) Upgraded the firmware to the latest 1.38.
4) Installed licences (2nd version - tv84), among them the 300MHz BW and it was accepted this time.
I realise now that I certainly did the mistake of install the 200MHz the first time I upgraded my scope and that disabled the possibility to reach the 300MHz back then.
So... avoid playing with lower bandwidth licences if you don't want to restart the hack process again.
But in the end, if it wasn't for my mistake, my scope would still be stuck in the 200MHz. Another lesson learned. I think
PS: Now I realize... the TEK P2220 and P2200 probes I was using with the scope, became "short". Any advise for some 300MHz probes?