You might try this:

https://support.na.sage.com/selfservice/viewdocument.do?noCount=true&externalId=10897&sliceId=2&isLoadPublishedVer=&docType=kc&docTypeID=DT_Article&stateId=7027&cmd=displayKC&dialogID=468162&ViewedDocsListHelper=com.kanisa.apps.common.BaseViewedDocsListHelperImpl&openedFromSearchResults=true

I would really suggest upgrading to a newer version.    We still sell perpetual programs.   We have very good pricing. In fact, we have price match guarantee.  Unlike some other sources selling Sage 50, Our Traditional Perpetual programs come with a Sage Business Care plan for one full year and an upgrade to Sage 50 2023 when released in 2022. We also have a price match guarantee.

[email protected]   304-233-2612

I have been running into a similar error message quite often  after upgrading to 2022.  It is a totally bogus error message and if I close peach tree and then reopen the error goes away.  

When you are ready to close the program, go to File > Exit.  It should not happen going forward if you close that way all the time. 

I'll try that.  The weird thing about the error message is that it never happens when I open a company.  It has only happened after I've been in a company doing some work and then go to run a backup before going onto a different company and it is at that point I have been getting the error message.