I had a weird issue that popped a couple of times. Ultimately, I ended up deleting all of the files in the tmp location and then the import worked with no issues. It was a weird issue. I also saw that the copy was working (if I deleted the file manually, a copy would show up even though there was a failure). After I dumped everything and got the import to work... I had no more issues.
Did you just delete the files in the mysql\data\tmp directory?
When I stop the WFA services these files are removed automatically. I then restarted the service. Tried to run the data acquistion, and it still fails.
This all started happening after I imported a custom workflow that was provided to us by Yaron. This workflow was for testing Cluster-Mode failover and added it's own dictionary entries. Unfortunately I didn't realize there were issues until after the 2 days of backups that WFA keeps.
Not being able to delete that dictionary object makes me think something happened to the custom tables within the database. I tried to open a NetApp case on this but because it is custom, they told me to resolve it through here.
I know this thread is pretty old but I've been having the same problems with WFA 3.0P1 on Windows Server 2012.
If there were any of the temporary .dump files in the temp directory my custom datasource aquisition would fail. I added this code to the beginning of the data source script to remove the .dump files before trying to acquire my datasource and things have been working well since:
Get-WFALogger -message ("Removing all .dump files from temporary directory")
$tempDir = "C:\Program Files\NetApp\WFA\jboss\standalone\tmp\wfa”
Get-ChildItem $tempDir *.dump | remove-item
Kudos for the suggestion on removing .dump files from the WFA temp directory before importing the datasource file - this worked perfectly! WFA v4.0
Previously my symptoms were; I'd create the datastource and initlal import would be successfull, so I'd think I was all set. But subsequent imports would fail with exactly the error described at the top of the thread.
I would like to add that if you're creating a cusom data source in WFA running on a Linux server, the path for the tmp directory is this:
I experienced the same error message as described in this thread, but the cause was different. The cause in my case was that the source filename contained upper-case letters. When I changed the source and destination filenames to be all lower-case letters, the data acquisition succeeded. Go figure!