This will result in no more patches and therefore no more security patches. Moreover, the current version of Office 2010 already has a security flaw since it requires the use of cypher known as WEAK (TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA)

We recommend that all GoFAST client organizations take the opportunity to switch to Onlyoffice and thus benefit from:

• co-authoring features
• avoid having to install (and update) an application on the PC
• to facilitate the use personal PC (useful in case of lockdown, at the hotel in emergency situation)
• have their data protected in the organization's datacenter or in sovereign SaaS (not subject to CloudAct as at Microsoft)
• significantly reduce costs, less than 20 euros / year (Onlyoffice works per open document and not per user, further optimizing the financial side)
• promote open-source and European sovereignty

It will therefore be sufficient to keep a few versions of MS-Office for departments needing complex macros and for which it is not possible to convert them to Onlyoffice macros.

Note that for the messaging part, it is possible to buy Outlook separately or switch to Thunderbird (Opensource which has an ActiveSync extension if you have MS-Exchange)