I have a RouterOS v3.30 with a AMD dual core 2,6 Ghz with 2GB RAM & 80 GB IDE HD for system & 80GB SATA HD for web-cache.

I use a transparent web proxy and I set Max. Cache Size = unlimited
then i close winbox, after a while, I open it again and Max. Cache Size is automatically setted to none... the cache still works, the navigation never cuts, but the cache function stop working while the Cache Used -space used on the disk- back to 0.

After that I manually disable the proxy, re-input the unlimited space, enable the proxy and he works again.... for a little time (maybe 1 day), when starting over the strange behaviour commented.

why this happens?

I change for second time the disk SATA, with another -previously I have a 320gb sata- (both news), and with the new 80gb sata disk I have the same results. At the same time, in other machine I did not get errors and the webproxy cache works great withouts these "resets".

Anybody knows whats happens?

I have seen this happen several times. For whatever reason, when your cache is functioning and you open the webproxy settings dialog box, sometimes the cache and some of the other settings revert to default and if you just only happen to look at your usage statistics and do not pay attention to your first page of the dialog box, you may select OK and that then accepts the new settings.

If you open this box to check your usage statistics, make sure you close it by using "cancel" or use the red X at the top of the dialog box, so nothing is saved. other than that, make sure you look at the first page each and every time you open this dialog box to make sure that nothing has reverted before you click accept.

RadioResearch

I agree. Your explanation is really what here happens.

Pressing "cancel" instead "ok" in the status tab is the better way to avoid this issue.

Thank you!