SQLiteException: Database file locked

[Hoogineer]

I set up an HTPC for my father-in-law with NextPVR installed on Windows XP using a Hauppauge DCR-2650 (although I regret not getting him the HDHomeRun Prime instead) and a Cisco tuning adapter. Unfortunately, I'm seeing SQLiteException (database file locked) everytime there seems to be a DB update. The main symptom that caused me to look into this was the EPG update not appearing to run after initial setup; however, perusing the logs indicates that the EPG update does appear to be taking place -- with listings download -- but they don't appear to be saved in the database, *except* when a manual EPG update is requested from the Settings menu. (I have not used anything to check the database.) When we examined the system last night, we also confirmed that the Recording service was running (both by examining the system tray and the Services control panel).

(1) What causes the SQLiteException? (I feel like sub mentioned a process locking the database and not letting go, but what would cause that?)
(2) Based on the attached logs, does that seem like the likely cause of EPG not being updated automatically?
(3) I asked my father-in-law to reboot the HTPC last night after we made some updates to the config (e.g., disabling "Update DVB EPG during live TV" in Settings: Misc, changing EPG update hour from 2 to 4 in Settings: Misc2), but I didn't talk to him tonight. Does that remove DB locks? Or do they persist beyond the offending process terminating? (I'm not familiar with the SQLite database.) I'd install the Firefox SQLite viewer, but I'm not going to ask someone who isn't a software engineer to make SQL queries remotely...

Thanks to all for your help.

[Graham]

The nrecord.log contains this ...

2012-12-11 18:59:02.968 [DEBUG][7] Started recording (911:1:C:\TV\Jeopardy!\Jeopardy!_20121211_19001930.ts)
2012-12-11 18:59:06.500 [DEBUG][8] Deleting old listings from Channel OID: 8491 (MTV2)
2012-12-11 18:59:12.283 [DEBUG][8] Deleting old listings from Channel OID: 8492 (FUSE)
2012-12-11 18:59:15.643 [DEBUG][8] Deleting old listings from Channel OID: 8493 (ANPT)
2012-12-11 18:59:20.050 [DEBUG][8] Deleting old listings from Channel OID: 8494 (truTV)
2012-12-11 18:59:24.380 [DEBUG][8] Deleting old listings from Channel OID: 8495 (HLN)
2012-12-11 18:59:27.740 [DEBUG][8] Deleting old listings from Channel OID: 8496 (SNY)
2012-12-11 18:59:32.694 [DEBUG][8] Deleting old listings from Channel OID: 8497 (N12TW)
2012-12-11 18:59:32.991 [ERROR][7] Unexpected error saving scheduled recording: System.Data.SQLite.SQLiteException: The database file is locked
database is locked

Try scheduling an EPG update to occur when there is no recording scheduled. For what it's worth, I always try and reboot as soon as possible after a database error.