Office Online Server Error Opening PDF File In SharePoint 2019 OnPrem

Question

Recently provisioned Office Online Server 2019 and SharePoint 2019. Users getting error message opening some PDF files. Its random where small PDF's seems to open fine but other PDF's not opening by Word Online. Getting following error in ULS log that I think is related to this issue.

WAC Persisted Cache Storage - Not enough disk space to write. Giving up.

Currently remove WordPDF bindings so that PDF's can be handled by browser. Seems like opening PDF's in Word Online is not reliable option.

New-OfficeWebAppsFarm -InternalURL "https://submain.domain.com"
-ExternalURL "https://submain.domain.com" -CertificateName "certname"
-EditingEnabled $true -LogLocation "Path to logs"
-CacheLocation "Path to cache" `
-RenderingLocalCacheLocation "Path to render cache"
-AllowCEIP
-CacheSizeInGB 30
-MaxMemoryCacheSizeInMB 1024

Answer 1

According to your description, smaller PDF files do not have such problems when opened.

And based on the error information you find, it also means that there is not enough memory.

Please note:

Low memory conditions can cause Office document previews to fail in Office Online.

More information:

Configure Office Online Server for SharePoint Server