PR4D resource damaged an no previous version available

So, this last week we finally upgraded our hosted client base from v16 to v17. We are in a scenario where our clients are hosted in MS RDS servers. Any given user, on any given login could hit 1 of several RDS servers, depending on user load balance. Each given RDS Server machine is hosting many client RDS sessions.

Some of our clients are getting the infamous “PR4D resource damaged…” message.

It seems to me that 4D had trouble removing an old cache file, or something.
What does this message really mean? and is there a preventative solution?

It seems like every time we upgrade major versions, we get some percent of our users that have this for a while.

: Tony RINGSMUTH

It seems to me that 4D had trouble removing an old cache file, or
something.

Possible. It also happens if your installation provides a way that two clients are using the same cache folder, not a unique one. Each client needs to use it’s own cache.

I think this issue is better to analyze in a TAOW case…

BTW, the cache folder is nothing else as a reduced database. Your RDS server could “copy” that folder with a login script for each session (and destroy it after). Copying a full folder on a local system is usually faster as requesting resource by resource via network. As said, each client needs its own exclusive (read/write) instance. If in doubt how to do that, contact tech support…