Trouble shooting issues with Lucid Builder

Having problems with Lucid Builder? Please check over these common causes.

1. Lucid Builder running slowly or the save and open operations are very slow.
A Virus or Malware scanner may be constantly checking the file and data operations of Lucid or the Java Runtime Environment (JRE).
Solution: Add Lucid’s executable (Windows) or JAR file (OSX/Linux) and the Lucid install folder to the scanners exceptions list. Please refer to your virus scanners help on how to do this.

2. Lucid Builder or the Lucid setup package doesn’t open.
Normally this is a Java Runtime Environment (JRE) problem – I.e., not installed, out of date, memory allocation restrictions or the JRE isn’t in the operating system environment path.

Solution: Update the to latest available JRE, free from: During the install ensure you elect to add the JRE to the system path. Check that you have enough available system memory to run Lucid, particularly if you are running a large number of other apps at the same time. Lucid’s memory requirements are generally quite small, though very large keys and keys with large media sets will require additional memory to process.
Note: To install Lucid, you need administrative rights on your computer. Please see your IT support for assistance, if your account doesn’t have this level of access.

3. Working directly on a cloud synchronised folder, network drive or an older USB stick drive.
Some cloud sync services can greatly slow and even interfere with file operations. Network drives can also be affected by network congestion and slow speeds. Older USB stick drives can be very slow and/or unreliable.

Solution: Try moving the key to another non-cloud/network drive based folder to see if this makes a difference.

4. The hard drive is failing or running out of space.

Solution: Check the hard drive health and available space, including the operating system drive. Try saving and constructing the key on a different drive.

5. Corrupt images within the key.
Lucid is often checking, loading and thumbnailing images held within the key. If one or more images are corrupt, it can greatly slow down these operations.

Solution: Determining problematic images can be difficult. Look for any images that are only partly ‘rendered’ or no thumbnail is present, or the thumbnail is all black or all white. This may indicate the larger image is corrupt. Another alternative is to batch process the images to optimise the file, via a third party graphics package (E.g., IrfanView or Photoshop or GIMP). Enabling logging within Lucid (see below) may also indicate problematic images in the log output.

6. Very large images – Lots of very large images (e.g. 5MB or greater) can be slow to process (for any application).

Solution: Normally such high quality/large images are not required (and are undesirable if the key is to be web based). Try optimising them (dimensions and file size) with a third-party graphics package (E.g., IrfanView or Photoshop or GIMP). We normally recommend the JPEG format, or PNG format, if background transparency is required. If the key is going to be deployed on the web, for the best end user experience we would recommend a longest side image dimension of no more than 1200px, targeting a file size less than 500kb. Ideally the file size would be less than 300kb.

Finally check that your Lucid Builder is up to date. See the update notification URL for the latest release information:

If none of the above has helped, check your operating system processes to examine CPU and hard drive consumption for Lucid (e.g. while saving etc) and other applications. (e.g., Task Manager). Is it excessive on one or more processes? If so, try closing the offending application.

Enable the logging feature in the Lucid Builder:

To enable logging do the following:

  1. Copy the ‘log4j.xml’ file from the Lucid install folder ‘resource’. I.e., ‘C:\Program Files\Lucid4\resource\log4j.xml’ to the root install folder. i.e., ‘C:\Program Files\Lucid4\’
  2. Next, edit the copied ‘log4j.xml’ file in a text editor such as Notepad++ (not MS Word).
  3. Look for a property named ‘basePath’ and edit the path to a location Lucid can write out a log file. The path/folder must exist and not be a restricted system location. Note the forward slashes, use these instead of back slashes regardless of operating system.

Next, run the Lucid Builder as usual – try saving and deploying etc. You should now see a file has been created in the base path location called ‘Lucid.log’.

Please send Lucid support this file (zipped), along with any other relevant information about your key and operating system for us to investigate further.