WHMCS on localhost using DesktopServer Problem

[GhostRider]

Hello there,

I've installed the most recent whmcs 8.3.0 on localhost, which is running DesktopServer.
During installation, there were no problems.
I followed the wizard's advice and deleted the install folder.
The front page is loading properly.
attempted to log in to the backend
The form is loaded, but when I try to login, I get the following error (I activated the $display errors setting in configuration.php).:

 

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TypeError: Return value of WHMCS\Support\TicketMask::gatherMaskPossibilities() must be of the type int, float returned in C:\whmcsdev.test\vendor\whmcs\whmcs-foundation\lib\Support\TicketMask.php:0
Stack trace:
#0 C:\whmcsdev.test\vendor\whmcs\whmcs-foundation\lib\View\Admin\HealthCheck\HealthCheckRepository.php(0): WHMCS\Support\TicketMask->gatherMaskPossibilities()
#1 C:\whmcsdev.test\vendor\whmcs\whmcs-foundation\lib\View\Admin\HealthCheck\HealthCheckRepository.php(0): WHMCS\View\Admin\HealthCheck\HealthCheckRepository->checkTicketMask()
#2 C:\whmcsdev.test\includes\api\gethealthstatus.php(0): WHMCS\View\Admin\HealthCheck\HealthCheckRepository->nonKeyChecks()
#3 C:\whmcsdev.test\vendor\whmcs\whmcs-foundation\lib\Api\V1\Api.php(0): unknown()
#4 C:\whmcsdev.test\vendor\whmcs\whmcs-foundation\lib\Api\V1\Api.php(0): WHMCS\Api\V1\Api->executeApiCall()
#5 C:\whmcsdev.test\includes\functions.php(0): WHMCS\Api\V1\Api->call()
#6 C:\whmcsdev.test\modules\widgets\Health.php(23): localAPI('GetHealthStatus', Array)
#7 C:\whmcsdev.test\vendor\whmcs\whmcs-foundation\lib\Module\AbstractWidget.php(0): WHMCS\Module\Widget\Health->getData()

Edited October 21, 2021 by GhostRider

[GhostRider]

Oops!
Something went wrong and we couldn't process your request.
Please go back to the previous page and try again.

For additional assistance, please reference the WHMCS TroubleShooting Guide »

TypeError: Return value of WHMCS\Support\TicketMask::gatherMaskPossibilities() must be of the type int, float returned in C:\whmcsdev.test\vendor\whmcs\whmcs-foundation\lib\Support\TicketMask.php:0
Stack trace:
#0 C:\whmcsdev.test\vendor\whmcs\whmcs-foundation\lib\View\Admin\HealthCheck\HealthCheckRepository.php(0): WHMCS\Support\TicketMask->gatherMaskPossibilities()
#1 C:\whmcsdev.test\vendor\whmcs\whmcs-foundation\lib\View\Admin\HealthCheck\HealthCheckRepository.php(0): WHMCS\View\Admin\HealthCheck\HealthCheckRepository->checkTicketMask()
#2 C:\whmcsdev.test\includes\api\gethealthstatus.php(0): WHMCS\View\Admin\HealthCheck\HealthCheckRepository->nonKeyChecks()
#3 C:\whmcsdev.test\vendor\whmcs\whmcs-foundation\lib\Api\V1\Api.php(0): unknown()
#4 C:\whmcsdev.test\vendor\whmcs\whmcs-foundation\lib\Api\V1\Api.php(0): WHMCS\Api\V1\Api->executeApiCall()
#5 C:\whmcsdev.test\includes\functions.php(0): WHMCS\Api\V1\Api->call()
#6 C:\whmcsdev.test\modules\widgets\Health.php(23): localAPI('GetHealthStatus', Array)
#7 C:\whmcsdev.test\vendor\whmcs\whmcs-foundation\lib\Module\AbstractWidget.php(0): WHMCS\Module\Widget\Health->getData()
#8 C:\whmcsdev.test\vendor\whmcs\whmcs-foundation\lib\Module\AbstractWidget.php(0): WHMCS\Module\AbstractWidget->fetchData(false)
#9 C:\whmcsdev.test\templates_c\fc6958cbc46fddb7b9de21efac33a6500145cc72_0.file.homepage.tpl.php(145): WHMCS\Module\AbstractWidget->render()
#10 C:\whmcsdev.test\vendor\smarty\smarty\libs\sysplugins\smarty_template_resource_base.php(123): content_61711cb55f85b7_80284528(Object(Smarty_Internal_Template))
#11 C:\whmcsdev.test\vendor\smarty\smarty\libs\sysplugins\smarty_template_compiled.php(114): Smarty_Template_Resource_Base->getRenderedTemplateCode(Object(Smarty_Internal_Template))
#12 C:\whmcsdev.test\vendor\smarty\smarty\libs\sysplugins\smarty_internal_template.php(216): Smarty_Template_Compiled->render(Object(Smarty_Internal_Template))
#13 C:\whmcsdev.test\vendor\smarty\smarty\libs\sysplugins\smarty_internal_templatebase.php(232): Smarty_Internal_Template->render(false, 0)
#14 C:\whmcsdev.test\vendor\smarty\smarty\libs\sysplugins\smarty_internal_templatebase.php(116): Smarty_Internal_TemplateBase->_execute(Object(Smarty_Internal_Template), NULL, NULL, NULL, 0)
#15 C:\whmcsdev.test\vendor\whmcs\whmcs-foundation\lib\Smarty.php(0): Smarty_Internal_TemplateBase->fetch('blend/homepage....', NULL, NULL, NULL, false, true, false)
#16 C:\whmcsdev.test\vendor\whmcs\whmcs-foundation\lib\Admin.php(0): WHMCS\Smarty->fetch('blend/homepage....')
#17 C:\whmcsdev.test\vendor\whmcs\whmcs-foundation\lib\Admin.php(0): WHMCS\Admin->output()