>One client was getting the "Not enough memory for file map" error on some machines and I confirmed that it can be resolved by using SYS(3050). However, is there a danger of setting the buffers too low? I had seen recommendations for 64*1024*1024 and 512*1024*1024 but the "512" was too high and I still got the error. Can there be any adverse effects by using SYS(3050)?

Definately yes -
if set too low (depending on physical RAM - danger of *lowered* perf, especially when indexing or using SQL)
if set too high (depending on physical RAM - danger of *lowered* perf)
if set too high (depending on physical+"swapfile" RAM - danger of runtime errors)

In very RAM heavy machines with comparably low swap file settings the default behaviour might evoke runtime errors as well - more in earlier versions of vfp.

HTH

thomas