Being used by another process ... when it's the only thing running!

[Gary Mugford]

The production Windows 7 machine died a week ago. After the initial shock, I've been madly trying to get the replacement, a Win 10 machine, up and running.

Doing Month End requires I convert a Paradox set of databases to Nexus through BDE2NX.exe, then I run a program that uses a LOT of queries against the Nexus data to kick out a spreadsheet and then an analysis of the Paradox data to get a second spreadsheet. The software has been working correctly for about seven years. Now, under the emergency conditions on the Win 10 machine, a problem. And it's with BDE2NX.exe, which is just a compiled version of the app that comes with NexusDB. It and the query-aplenty application both have NexusDB embedded. I also verify the Paradox data is free of corruption before exporting.

It seems randomly, the BDE2NX app stopped exporting the data of 45 of the 232 databases. Every stoppage was after some number of hundreds of the records. Some times after 100, at the most annoying after 120,000. Here's one specific example dealing with the WARNINGS database ...

2020-12-02 00:37:22 Information
Source Table: WARNINGS.DB
New table pair: "WARNINGS.DB" ---> "WARNINGS"
 
2020-12-02 00:37:22 Information
Source Table: WARNINGS.DB
Creating new table
 
2020-12-02 00:37:22 Information
Source Table: WARNINGS.DB
Data transfer started
 
2020-12-02 00:37:23 Information
Source Table: WARNINGS.DB
3700 records transfered
 
2020-12-02 00:37:23 Error
Source Table: WARNINGS.DB
Data transfer failed due to error
NexusDB: <unnamed TnxDatabase instance>: INTERNAL: File could not be opened [T:\_Source_FakeMTD\Nexus2\WARNINGS.nx1, error 32, The process cannot access the file because it is being used by another process] [$2405/9221]

Here's the end of the log ... Note the stats coming BEFORE the final logging of the ZebraOperations export logging!

2020-12-02 01:27:15 Information
Source Table: ZebraOperations.DB
New table pair: "ZebraOperations.DB" ---> "ZebraOperations"
 
2020-12-02 01:27:15 Information
Source Table: ZebraOperations.DB
Creating new table
 
2020-12-02 01:27:15 Information
Source Table: ZebraOperations.DB
Data transfer started
 
2020-12-02 01:27:15 Information
Source Table: ZebraOperations.DB
0 records transfered
 
2020-12-02 01:27:15 Statistics
232 tables processed
187 transfers succeded
45 transfers failed
 
2020-12-02 01:27:15 Information
Source Table: ZebraOperations.DB
The query list was empty

Does this mean the app is multi-threaded and got ahead of itself???

Lastly, I backed up and deselected all databases and then tried JUST Warnings ...

2020-12-02 01:35:09 Information
Source Table: 
Transfer environment check started
 
2020-12-02 01:35:09 Information
Source Table: 
Transfer operation started
 
2020-12-02 01:35:09 Information
Source Table: WARNINGS.DB
New table pair: "WARNINGS.DB" ---> "WARNINGS"
 
2020-12-02 01:35:09 Information
Source Table: WARNINGS.DB
Creating new table
 
2020-12-02 01:35:09 Error
Source Table: WARNINGS.DB
Table creation failed due to error
Access violation at address 00898F94 in module 'BDE2NX.exe'. Read of address FFFFFFFC
 
2020-12-02 01:35:09 Statistics
1 tables processed
0 transfers succeded
1 transfers failed
 
2020-12-02 01:35:09 Information
Source Table: WARNINGS.DB
The query list was empty

Now, an access violation error. And the whole sequence repeated itself with a freshly rebooted computer.

I DID restart the computer with a hard reboot. The only thing running is the default detritus of what runs. NONE of them, to the best of my knowledge, are BDE or NexusDB using applications. Plus, OTHER databases, with many more records and much more data with more fields, WORK AS EXPECTED.

There IS one issue I wasn't able to get around. The destination of the dead Win 7 machine was drive T. I don't have a drive T on the new machine, so I put in a blank thumbdrive with 10 times the size I need and had it set to drive T to receive the NexusDB data.

Any ideas of what is going on??? On a bit of a tight schedule. So I'm panicking a bit. I really do not understand the error. How can it not find the TnxDatabase instance, yet import a portion of the records??? ANd the error 32 just doesn't make any sense whatsoever. At least to me.

On 02/12/2020 06:38, Gary Mugford wrote:
> The production Windows 7 machine died a week ago. After the initial
> shock, I've been madly trying to get the replacement, a Win 10 machine,

My guess is Windows 10 in build anti-virus (Defender). Have you excluded
the source & destination directories of your app from it's on access
scanning ?

Cheers

David

[Gary Mugford]

Originally Posted by David Rose

On 02/12/2020 06:38, Gary Mugford wrote:
> The production Windows 7 machine died a week ago. After the initial
> shock, I've been madly trying to get the replacement, a Win 10 machine,

My guess is Windows 10 in build anti-virus (Defender). Have you excluded
the source & destination directories of your app from it's on access
scanning ?

Cheers

David

Honestly, I've stayed away from Win10 because of Big Brother crap like Defender. I do have a pro Webroot anti-virus on the machine, but I'm leery of not letting the AV checkout my programming ... it's got infected about 23 years ago when a Delphi virus got through to me so I tend to remember a Looooong time. On the other hand, I plan to switch to ESet after Christmas. I hate the Webroot interface now that I've seen it in action. It's certainly worth it to at least turn it off for a trial. And if it works, I can follow up with your full suggestion. Thanks for taking the time to help out an old stick in the mud.

Be safe. GM

[Gary Mugford]

It's troubling David Rose, but you were right. Indeed, turning off AV's interference in the folders my NexusDB/BDE app was using turned out to allow the app to run successfully.

I put off the test trying to revive the old work machine but that proved a waste of time, money, stress and work. Emphasize the stress lost. So, I approached re-testing the App with dread. And indeed, when I tried to run it with ONLY the one database selected, it threw a memory violation. With no reason to do it, other than to say I did, I went back a tab, selected all the databases and hit the Import button. And slowly, it worked!! All 232 databases exported/imported (depending on POV) successfully.

This allowed me to do MonthEnd and, that's a major, major relief. So, THANK YOU David.

I can look forward to being able to do that again at THIS month's end. AND in the meantime, I can workaway at setting up the new work machine without the Sword of Damocles hanging over my head. THANK YOU for that too.

GM

On 05/12/2020 09:45, Gary Mugford wrote:
> It's troubling David Rose, but you were right. Indeed, turning off AV's

> This allowed me to do MonthEnd and, that's a major, major relief. So,
> THANK YOU David.
>

No problem. I've experienced this many times. I keep meaning to write a
server extension that drops eicar.com in to the data folder and then
checks if it still exists. If it doesn't then chances are some
anti-virus has deleted it.

David