Find below some collection of topics related to Incompatibilities, Bugs, Requested Features and special Behavior of WHMCS worth to know.
Illegal Mix of Collations
You may receive this error when opening the addon in the WHMCS Admin Area. This can happen on older WHMCS installations where database updates between WHMCS upgrades did not go smoothly, leaving some tables in a different collation. To solve this issue, it is necessary to convert the affected tables to the correct default collation, with a command like this:
ALTER TABLE tblexample CONVERT TO CHARACTER SET utf8 COLLATE utf8_unicode_ci;
Where tblexample should be replaced by the affected table. IMPORTANT: please backup your database befor making any changes! More information can be found in this WHMCS article
Change of Registrant
When it comes to a change of owner while updating whois contact information of a domain, this might lead to a so-called Trade. This is in general for free, except at some ccTLD providers. In case this results into costs, we log such costs to the System Activity Log for transparency. WHMCS is by design totally incompatible to this process and can’t therefore automatically generate an invoice for this (and to process the update after payment). We are trying to figure a better solution out. A Feature Request has been addressed to WHMCS as well.
Registrar-Lock Configuration
Registrar-Lock isn’t supported by all TLDs/TLD providers. Registrars have therefore to implement a manual workaround for getting the menu item removed and the warning about the domain being unlocked removed. This should be better covered by a TLD-based configuration setting (like the one for epp code). A Feature Request has been addressed to WHMCS.
IDN Conversion
Reported to and confirmed by WHMCS (-> #CORE-17342). When it comes to IDNs, WHMCS is doing the conversion to punycode incorrect. There are different standards - IDNA2003, IDNA2008, UTS46. It depends on the underlying TLD provider / registry which one to support. e.g. when searching for fußball, fussball.com is the right way for .com and fußball.de the right one for .de, but WHMCS is converting it to fussball.de which is still supported and valid, but probably not the domain you were looking for (fußball.de). This is affecting all registrar integrations.
EPP Codes
Some TLDs like .DK, .AT, etc. do not require an epp / authorization code for transfers. That’s why we automatically disable the “epp code” checkbox for such TLDs within the “Registrar TLD Sync” (WHMCS’ pricing import). But when it comes to a system-internal transfer in the HEXONET System, so from customer A to customer B, our Backend System is enforcing the epp / authorization code which is not compatible to the global configuration setting. Workaround: Deactivation of the global configuration. Which is then enforcing the authcode for all transfer cases of the underlying TLD and therefore also not what we are looking for. If a transfer is failing, check the Module Queue (find it under utilities) if there’s an error message including “Authorization failed; USERTRANSFER - AUTH CODE REQUIRED”. If so, please ask the current owner for the epp code and then reach out to our support department. We have addressed a feature request to WHMCS to get this solved.
Local Presence Service
WHMCS isn’t offering a Domain Add-On to cover a Local Presence Service (aka. Trustee Service). This would definitely increase selling of ccTLDs. Furthermore, if you’re manually importing Domains to WHMCS with activated Local Persence Service on Registrar-side, it won’t get invoiced in WHMCS. A Feature Request has been addressed to WHMCS.
Registrar TLD Sync Automation
Importing TLD Settings and Prices using WHMCS’ Feature “Registrar TLD Sync” got released, but without the option to automatically schedule it via cron. A Feature Request has been addressed to WHMCS.
Importing TLD registration terms and renewal terms
For some registries, registration terms do not match to available renewal terms at all (or partially). Such TLDs can't be correctly imported via Registrar TLD Sync and need a manual configuration via "System Settings" > "Domain Pricing".
Although this is supported by our major Reseller Brands, WHMCS doesn't have enough flexibility to support this via Registrar TLD Sync. WHMCS assumes that TLDs entirely match regarding their registration and renewal terms. That's why it is importing the pricing accordingly: Price per term = price * term and this for Registration and Renewal. This isn't ideal.
A Feature Request has been raised with WHMCS to address this issue.
Until WHMCS addresses this deficiency, the workaround is to manually reconfigure these TLDs after import.
Function Deprecations
Reported to and confirmed by WHMCS (-> #CORE-17038). The developer documentation for Registrar Modules is pointing out function GetDomainInformation to be integrated instead of the deprecated functions GetNameservers and GetRegistrarLock. We just run into issues after removing these deprecated functions and re-alived them again. Find the whole related issues and topic documented here. This isn’t affecting you as reseller or your customers. But, when patched by WHMCS, would increase the performance of our integration.
localAPI GetTLDPricing
Reported to and confirmed by WHMCS (-> #CORE-16920). This API Command is not returning prices that are set to 0.00. Not affecting our Integration, just something we addressed to WHMCS.
localAPI DomainRequestEPP
Reported to WHMCS, but not confirmed as bug. So let us see it as strange behavior. The epp code returned has to be html decoded. Not affecting our Integration.