If Ubuntu Software Center closes a few seconds after opening, then the solution given in this tutorial may help you fix this problem. Here are some outputs returned from the terminal when the application crashes:
File "/usr/share/software-center/softwarecenter/ui/gtk3/views/appdetailsview.py", line 176, in __init__
AttributeError: 'ProgressBar' object has no attribute 'set_data'
To solve this problem, you can follow these instructions:
1. Open the terminal and edit this file:
sudo gedit /usr/share/software-center/softwarecenter/ui/gtk3/views/appdetailsview.py
2. Locate this line (line 176):
Comment it (add the # sign at the beginning of the line to disable it), then save your file and exit.
NOTE: This solution is workable under Ubuntu 12.04/11.10 or older.