Database Exception Error Calibre

CAlibre Version 08.47 Linux Fedora

I have multiple libaries

When carrying out some house keeping and moving files from one to another, my linux version crashed out with an OPEN DATABASE ERROR

Upon login I found all my libaries missing from the Libary tab and was unable to carry out any comand under the tab.

I deleted the data file in the libary file created a new one and my libaries reappeared and I ould move around as normal.

REbuilding the database produces this error

Traceback (most recent call last):
File "site-packages/calibre/gui2/actions/choose_library.py", line 356, in restore_database
File "site-packages/calibre/gui2/ui.py", line 536, in library_moved
File "site-packages/calibre/gui2/tag_browser/view.py", line 143, in set_database
File "site-packages/calibre/gui2/tag_browser/model.py", line 258, in set_database
File "site-packages/calibre/library/prefs.py", line 58, in set
File "site-packages/calibre/library/prefs.py", line 53, in __setitem__
File "site-packages/calibre/library/sqlite.py", line 314, in run
DatabaseException: unable to open database file
RemoteTraceback (most recent call last):
File "site-packages/calibre/library/sqlite.py", line 271, in run
OperationalError: unable to open database file

I have deleted calibre, reinstalled in another directory, just in case it was a corrupted libary file in the program and still no joy.

The last try at rebuilding a database had this effect, libary tab showing 0 books, books listed, able to view book and meta data but with error
calibre, version 0.8.47
ERROR: Unhandled exception: <b>DatabaseException</b>:unable to open database file
RemoteTraceback (most recent call last):
File "site-packages/calibre/library/sqlite.py", line 271, in run
OperationalError: unable to open database file

Traceback (most recent call last):
File "site-packages/calibre/gui2/metadata/single.py", line 458, in accept
File "site-packages/calibre/gui2/metadata/single.py", line 432, in apply_changes
File "site-packages/calibre/gui2/metadata/basic_widgets.py", line 95, in commit
File "site-packages/calibre/library/database2.py", line 2347, in set_title
File "site-packages/calibre/library/database2.py", line 2330, in _set_title
File "site-packages/calibre/library/sqlite.py", line 314, in run
DatabaseException: unable to open database file
RemoteTraceback (most recent call last):
File "site-packages/calibre/library/sqlite.py", line 271, in run
OperationalError: unable to open database file

Attempt to change libary produces this error

calibre, version 0.8.47
ERROR: Unhandled exception: <b>DatabaseException</b>:unable to open database file
RemoteTraceback (most recent call last):
File "site-packages/calibre/library/sqlite.py", line 271, in run
OperationalError: unable to open database file

Traceback (most recent call last):
File "site-packages/calibre/gui2/actions/choose_library.py", line 441, in qs_requested
File "site-packages/calibre/gui2/actions/choose_library.py", line 421, in switch_requested
File "site-packages/calibre/gui2/ui.py", line 535, in library_moved
File "site-packages/calibre/gui2/library/views.py", line 529, in set_database
File "site-packages/calibre/gui2/library/views.py", line 354, in save_state
File "site-packages/calibre/gui2/library/views.py", line 348, in write_state
File "site-packages/calibre/library/prefs.py", line 58, in set
File "site-packages/calibre/library/prefs.py", line 53, in __setitem__
File "site-packages/calibre/library/sqlite.py", line 314, in run
DatabaseException: unable to open database file
RemoteTraceback (most recent call last):
File "site-packages/calibre/library/sqlite.py", line 271, in run
OperationalError: unable to open database file

Any help would be apprecieated is this driving me up the wall, normally I find Calibre a very stable software but this problem is making me think of changing