Title: Error message: Uncaught Error: Undefined constant
Last modified: October 19, 2023

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# Error message: Uncaught Error: Undefined constant

 *  Resolved [andynz](https://wordpress.org/support/users/andynz/)
 * (@andynz)
 * [2 years, 7 months ago](https://wordpress.org/support/topic/error-message-uncaught-error-undefined-constant/)
 * I have recently upgraded to WordPress 6.3.2 and WP Photo album 8.5.01.007 and
   receive the following warning message:
   An error of type E_ERROR was caused in
   line 1838 of the file /home/zwaibops31482nz/subdomains/rotorua.waibopscd.org.
   nz/wp2021/wp-content/plugins/wp-photo-album-plus/wppa-common-functions.php. Error
   message: Uncaught Error: Undefined constant “WPPA_UPLOAD_PATH” in /home/zwaibops31482nz/
   subdomains/rotorua.waibopscd.org.nz/wp2021/wp-content/plugins/wp-photo-album-
   plus/wppa-common-functions.php:1838 Stack trace: #0 /home/zwaibops31482nz/subdomains/
   rotorua.waibopscd.org.nz/wp2021/wp-content/plugins/wp-photo-album-plus/wppa-cache.
   php(386): wppa_delete_obsolete_tempfiles()and then a lot more trace entries.Note
   the following:– The error occurs when switching to Maintenance mode via the Lightstart
   plugin.– The error does not occur if I deactivate WP Photo Album Plus– Apart 
   from that, the website appears to operate correctly.
 * Any ideas what may be the cause?
 * Regards
   Andy
    -  This topic was modified 2 years, 7 months ago by [andynz](https://wordpress.org/support/users/andynz/).

Viewing 3 replies - 1 through 3 (of 3 total)

 *  Plugin Author [Jacob N. Breetvelt](https://wordpress.org/support/users/opajaap/)
 * (@opajaap)
 * [2 years, 7 months ago](https://wordpress.org/support/topic/error-message-uncaught-error-undefined-constant/#post-17135372)
 * Sorry but i can not reproduce this on my dev site. I installed the Lightstart
   plugin, and i can switch to Maintenance mode without problems.
 *  Thread Starter [andynz](https://wordpress.org/support/users/andynz/)
 * (@andynz)
 * [2 years, 7 months ago](https://wordpress.org/support/topic/error-message-uncaught-error-undefined-constant/#post-17137563)
 * Thanks for taking the trouble to try and replicate the problem. 
   I did some further
   tests and it is ‘possible’ that the problem occurs when using the block editor
   on the Lightstart maintenance page – but goodness know how WP photo album gets
   involved.Anyway, I can do without Lightstart (now deleted), but cannot do without
   WP photo album.
 * Tried to make a donation (you have also helped a few times in the past), but 
   it seems that PayPal has restrictions on payments to other countries.
 * Andy
 *  Plugin Author [Jacob N. Breetvelt](https://wordpress.org/support/users/opajaap/)
 * (@opajaap)
 * [2 years, 7 months ago](https://wordpress.org/support/topic/error-message-uncaught-error-undefined-constant/#post-17137835)
 * What is/are the currenc(y)/(ies) in your PayPal account?

Viewing 3 replies - 1 through 3 (of 3 total)

The topic ‘Error message: Uncaught Error: Undefined constant’ is closed to new replies.

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 * 3 replies
 * 2 participants
 * Last reply from: [Jacob N. Breetvelt](https://wordpress.org/support/users/opajaap/)
 * Last activity: [2 years, 7 months ago](https://wordpress.org/support/topic/error-message-uncaught-error-undefined-constant/#post-17137835)
 * Status: resolved