Fyi I have the same issue and after some digging this is what I found:
In the flash uploader.php the variable $_POST['auth'] is wrong.
The variable is like this: "A D U1lp0Bw9..."
while the actual db entry looks like this: "A+D+U1lp0Bw9..."
So the plus signs ("+") are missing and instead replaced by whitespaces (" "). This happened on two different users, others had no plus sign and there it worked out of the box.
My temporary "fix" was to add
$hash = str_replace(" ", "+", $hash);
in "zenphoto\zp-core\zp-extensions\uploader_flash\uploader.php" on line 9.
Hope this helps you track down the root of the issue...
Comments
In the flash uploader.php the variable $_POST['auth'] is wrong.
The variable is like this: "A D U1lp0Bw9..."
while the actual db entry looks like this: "A+D+U1lp0Bw9..."
So the plus signs ("+") are missing and instead replaced by whitespaces (" "). This happened on two different users, others had no plus sign and there it worked out of the box.
My temporary "fix" was to add
$hash = str_replace(" ", "+", $hash);
in "zenphoto\zp-core\zp-extensions\uploader_flash\uploader.php" on line 9.
Hope this helps you track down the root of the issue...
Also note that the flash uploader will not be part of the next major release 1.4.5 anymore.