Hello.Thank you for your time with trying to help me.

sure, hopefully we can figure something out

what version are you using?

10.0

and the startup hang appeared just recently?

Yes. Perhaps a couple of hours ago.

Having said that, I hadn't used mathematica in several days so I am not sure if this would have occurred days ago

I do suspect the paclet issue I linked to, but there probably is something in addition to that

Yes. Likely. My first hurdle is reactivation!

you deleted both /usr/share/Mathematica and ~/.Mathematica ?

I recvd about a dozen emailsfrom wolfram in the last two days with various activation keys. I have tried them all. no avail

Let me check if those folders/files still exist

I again reinstalled it so these exist

both locations are writable by Mathematica? do they contain anything?

/usr/share/Mathematica contains Installer which is an empty folder

~/.Mathematica contains many items: Applications Autoload FrontEnd Kernel Licensing Logs Paclets SystemFiles

could you delete the Paclets directory

and then try starting the FE again/

I'm not sure if these locations are writable by mma. I will rm -rf the Paclet directory.

would you recommend that I start FE by "Mathematica" or should I do something else?

aahaa! I have the activation window now AFTER deleting Paclet directory and launching Mathematica

that's some progress

hopefully you have the licensing information handy

I have just used all the license activation keys I recvd last two days - none work! Is there someway I can find out current license number?

"There was runtime error in the product activation component"

What do you know... it just worked! (activation key: re-entering it and using manual activation)

okay, this is good

Tried launching mathematica again... same issue

ok, but now that you are activated

try the standalone kernel

and PacletUpdate["CloudObject"]

Ok... it just says: Paclet[CloudObject, 10.3.760, <>]

Is that supposed to be followed with something else?

no, that's what the result should look like

does the FE start now?

It certainly does! (tried and re-tried to ensure)

That was strange and inconvenient but I appreciate and am grateful for the help

happy to hear it worked!

and I am sorry for the inconvenience, this paclet was an unfortunate oversight

Well as long as "what doesn't kill us makes us stronger..."

I will say that Mathematica has so far been beating the living daylights out of MATLAB, Hypermesh and Ansys for continuum mechanics problems and I really like using it to expose my students to a better way! If you do work for the folks at Wolfram, I thank you for your diligence in creating a powerful tool

if you ever need to clear your $UserBaseDirectory, I'd suggest backing up the Licensing/mathpass file

restoring it later would avoid losing the activation

just backed it up. I suppose it would work until next activation cycle only though?

yes, until the next version is installed

Ok. That is good. thank you

thanks for the kind words, we are all passionate about Mathematica

have a good night/evening/day depending on your time zone

I hope to get my students more engaged in using Mathematica. you have a good night too.